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Everyday Science – Made Simple


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Contents

Topic Page No

1. Abbreviations 01

2. Units 04

3. Discoveries/Inventions 06

4. Measuring Tools 08

5. MCQS Material 10

6. Scientific Reasons 30

7. Differences 41

8. Short/Long Notes 69

 

1. Abbreviations

1. LPG: Liquefied Petroleum Gas

2. TNT: Tri Nitro Toluen

3. RNA: Ribonucleic Acid

4. CNG: Compressed Natural Gas

5. ATP: Adenosine Tri Phosphate

6. RBC: Red Blood Cells/Corpuscles

7. ECG: Electro Cardio Gram

8. PVC: Poly vinyl Chloride

9. RAM: Random Access Memory

10. CFC: Chloro Fluoro Carbon

11. LASER: Light Amplification by Stimulated emission of Radiation

12. RADAR: Radio Detection And Ranging

13. AIDS: Acquired Immune Deficiency Syndrome

14. ROM: Read Only Memory

15. LAN: Local Area Network

16. WWW: World Wide Web

17. DNA: Deoxyribonucleic Acid

18. SONAR: Sound Navigation And Ranging

19. SARS: Severe Acute Respiratory Syndrome

20. NTP: Network Time Protocol/ Normal Temperature and Pressure

21. RQ: Respiratory Quotient

22. NPN: Negative Positive Negative

23. PNP: Purine Nucleoside Phosphorylase

24. WAN: Wide Area Network

25. CPU: Central Processing Unit

26. BCG: Bacillus Calmette Guerin

27. STP: Standard Temperature And Pressure/Shielded Twisted Pair/Sodium

Tripolyphosphate/Spanning Tree Protocol

28. ATP: Adenosine Triphosphate

29. KWh: Kilo Watt Hour

30. BTU: British thermal Unit

31. LDL: Low Density Lipoprotein

32. MAF: Million Acre Feet

33. HDL: Hardware Description Language

34. MCV: Mean Corpuscular Volume

35. UHF: Ultra High Frequency

36. LED: Light emitting Diode

37. LCD: Liquid Crystal Display

38. BASIC: Beginner‘s All-Purpose Symbolic Instruction Code

39. MASER: Microwave Amplification by Stimulated Emission of Radiation

40. ETT: Educational Telecommunications and Technology/ European Transaction on

Telecommunication

41. HST: High Speed Technology/ High Speed Train (in UK)/Hubble Space Telescope

42. DBS: Data Base Server/ Direct Broadcast Satellite

43. CRO: Cathode Ray Oscilloscope

44. BOT: Build, Operate and Transfer/Botulinum Toxin

45. AMU: Atomic Mass Unit

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46. EMF: Electro Motive force

47. ADH: Anti-diuretic Hormone

48. GeV: Giga Electro Volt

49. CRT: Cathode Ray Tube

50. CNS: Central Nervous System

51. PTFE: Poly Tetra Fluoro Ethylene

52. GUT: Grand Unified Theory

53. LONAR: Long Range Navigation

54. MeV: Mega Electron Volt/ Million Electron Volt/ Multi-experiment Viewer

55. AWACS: Airborne Warning and Control System 56. CCTV: Closed-Circuit Television

1. ABM: Anti-Ballistic Missile

2. AC: Alternating Current/Air Conditioning

3. AEC: Atomic Energy Commission

4. Alt: Altitude

5. am: Ante Maridiem (Before Noon/Midday)

6. Amp: Ampere

7. APTEC: All Pakistan Technology Engineers Council

8. ATM: Automated Teller Machine (Banking)

9. AW: Atomic Weight/ Asia Watch

10. BIOS: Basic Input Output System

11. BDS: Bachelor Of Dental Surgery/ Bomb Disposal Squad

12. BP: Blood Pressure/ Boiling Point/ Blue Print 13. C/A: Current Account

14. CAA: Civil Aviation Authority

15. CABB: Centre Of Agricultural Biochemistry And Biotechnology 16. CAD: Computer-

Aided Design

17. Cal: Calorie

18. CD: Compact Disc/ Civil Defence/ Community Development

19. CD-ROM: Compact Disc Read-Only Memory

20. CECP: Cotton Export Corporation Of Pakistan

21. CHASNUPP: Chashma Nuclear Power Plant

22. CMCC: China Mobile Communications Corporation

23. COM: Computer Aided Manufacturing

24. COMSAT: Communications Satellite Corporation

25. COMSTECH: Council Of Scientific And Technology Cooperation Of Islamic Conference

26. CSIRO: Commonwealth Scientific And Industrial Research Organisation

27. CTBT: Comprehensive Test Ban Treaty

28. CT-Scan: Computerised Axial Tomography Scanning

29. DVD: Dynamic Versatile Disc

30. ECAT: Engineering Colleges Admission Test

31. EDB: Engineering Development Board

32. EEG: Electroencephalogram

33. ENERCON: Energy Conservation Centre

34. EPA: Energy Protection Agency

35. EPD: Energy Protection Department

36. ESA: European Space Agency

37. ESRO: European Space Research Organisation

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38. FAT: File Allocation Table

39. FCPS: Fellow Of The Royal College Of Physicians And Surgeons

40. FM: Frequency Modulation

41. FMCT: Fissile Material Cut-Off Treaty

42. FRCS: Fellow Of The Royal College Of Surgeons

43. GHz. Gigahertz

44. GMT: Greenwich Mean Tim

45. HIV: Human Immune Deficiency Virus

46. HTML: Hypertext Mark-Up Language

47. HTTP: Hypertext Transfer Protocol

48. IAEA: International Atomic Energy Agency (UN)

49. IBM: International Business Machine

50. IC: Integrated Circuit/ Intelligence Corps

51. ICBM: Inter-Continental Ballistic Missile

52. ICU: Intensive Care Unit

53. IEA: International Energy Agency

54. INSTRAW: International Research And Training Institute For The Advancement Of

Women

55. INTELSAC: International Telecommunications Satellite Consortium

56. Intelsat: International Telecommunications Satellite Organisation

57. IRBM: Intermediate Range ballistic Missile

58. ISP: Internet Service Provider

59. IT: Information Technology

60. ITB: Information Technology Board

61. JAXA: Japan Aerospace Exploration Agency

62. KANUPP: Karachi Nuclear Power Plant

63. KAPCO: Kot Adu Power Company

64. kHz: Kilohertz

65. KV: Kilo Volt

66. kW: Kilowatt

67. MCAT: Medical Colleges Admission Test

68. MDS: Master In Dental Surgery

69. MNP: Mobile Number Probability

70. MRBM: Medium Range Ballistic Missile

71. MRCP: Member Of Royal College Of Physicians

72. MRCS: Member Of Royal College Of Surgeons

73. MRI: Magnetic Resonance Imaging

74. MS: Medical Superintendent

75. MSN: Microsoft Network

76. MW: Megawatt

77. NADRA: National Database And Registration Authority

78. NEPRA: National Electric Power Regulatory Authority

79. NM: Nautical Mile

80. NMD: National Missile Defence

81. NPT: Non-Nuclear Proliferation Treaty

82. NRA: Nuclear Regulatory Authority

83. OGRA: Oil And Gas Regulatory Authority

84. NWD: Nation Wide Dialling

85. OGDC: Oil And Gas Development Corporation

86. pm: Post Meridiem

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87. PEMRA: Pakistan Electronic Media Regulatory Authority

88. PTA: Pakistan Telecommunication Authority

89. RADAR: Radio Detection and Ranging

90. SALT: Strategic Arms Limitation Talks

91. SLV: Satellite Launch Vehicle

92. SMS: Short Message Service

93. SNGPL: Sui Northern Gas Pipelines Limited

94. SONAR: Sound Navigation And Ranging

95. SSGPL: Sui Southern Gas Pipeline Limited

96. STD: Subscriber‘s Trunk Dialling

97. STM: Subscriber Identification

98. SUPARCO: Space And Upper Atmosphere Research Committee (Pakistan)

99. TB: Tubercle Bacillus/ Tuberculosis

100. UHF: Ultra High Frequency

101. UNAEC: United Nations Atomic Energy Commission

102. UNESCO: United Nations Education, Scientific And Cultural Organisation

103. VCD: Video Compact Disc

104. VHF: Very High Frequency

105. WAN: Wide Area Network

106. WAP: Wireless Application Protocol

107. WAPDA: Water And Power Development Authority

108. WHO: World Health Organisation

109. WMD: Weapons Of Mass Destruction

110. WWF: World Wildlife Fund

111. ZPG: Zero Population Growth

2. Units

1. Force: Newton/ Dyne

2. Temperature: Kelvin/ Celsius/ Degree

3. Current: Ampere

4. Heat: Joule/ Calorie/ BTU

5. Pressure: Pascal/Torr

6. Radioactivity: Becquerel/Curie/Rutherford

7. Atomic energy: Rydberg/Joule

8. Voltage: Volt

9. Electric Potential Difference: Volt

10. Electric Charge: Coulomb

11. Power: Watt

12. Resistance: Ohm

13. Conductivity: Mho

14. Energy: Joule/ Erg

15. Distance Between Stars And Planets: Light Year

16. Wavelength: Angstrom

17. Volume: Acre-Foot/Litre

18. Frequency: Hertz

19. Rate of flow of water: Cusec

20. Length: Meter/Fermi/Parsec

21. Optical Power Of A Lens or A Curved Mirror: Dioptre

22. Plane Angle: Radian

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23. Luminous Intensity: Candela

24. Amount of Substance: Mole

25. Rate Of Decay Of Radioactive Material: Rutherford

26. Sedimentation Rate: SVEDBERG Unit

27. Induction: Henry

28. Magnetic flux: Maxwell/ Weber

29. Magnetic Flux Density/Magnetic Inductivity: Telsa/Gauss

30. Electric Conductance: Siemens

31. Angle: Degree

32. Solid Angle: Steradian

33. Torque: Foot-Pound

34. Mass: Slug

35. Volume of Water Reservoirs: Acre-foot

36. Mechanical work/Energy: Erg

37. Magneto Motive Force: Gilbert

38. Newton: Force

39. Dyne: Force

40. Kelvin: Temperature

41. Celsius: Temperature

42. Degree: Temperature

43. Ampere: Current

44. Joule: Heat/Atomic Energy/Energy

45. Calorie: Heat

46. BTU: Heat

47. Pascal: Pressure

48. Torr: Pressure

49. Becquerel: Radioactivity

50. Curie: Radioactivity

51. Rutherford: Rate Of Decay Of Radioactive Material/Radioactivity

52. Rydberg: Atomic Energy

53. Volt: Voltage/Electron Potential Difference Coulomb: Electric Charge

55. Watt: Power

56. Ohm: Resistance

57. Mho: Conductivity

58. Erg: Energy

59. Light Year: Distance Between Star

60. Angstrom: Wavelength

61. Litre: Volume

62. Acre Foot: Volume

63. Hertz: Frequency

64. Cusec: Rate Of Flow Of Water

65. Meter: Length

66. Fermi: Length

67. Parsec: Length

68. Dioptre: Optical Power Of Lens

69. Radian: Plane Angle

70. Candela: Luminous Intensity

71. SVEDBERG: Sedimentation Rate

72. Henry: inductance

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73. Maxwell: Magnetic Flux

74. Weber: Magnetic Flux

75. Tesla: Magnetic Flux Density/Magnetic Inductivity

76. Gauss: Magnetic Flux Density/Magnetic Inductivity

77. Siemens: Electric Conductance

78. Degree: Angle

79. Steradian: Solid Angle

80. Foot Pound: torque

81. Slug: Mass

3. Discoveries/Inventions-Scientists Past Papers

1. Structure Of DNA: Watson & Crick

2. Rabies Vaccination: Louis Pasteur

3. Penicillin: Alexander Fleming

4. Genetic Laws of Heredity: Mendel

5. Vaccination Against Small Pox: Edward Jenner

6. Solar System: Copernicus

7. Current Electricity: Volta

8. Telephone: Graham Bell

9. Gramophone: Thomas Edison

10. Atomic Number: Mosley

11. Mercury Thermometer: Fahrenheit

12. Dynamite: Alfred Noble

13. Cell: Robert Hooke

14. Television: John Baird

15. X-rays: Roentgen

16. Circulation Of Blood: William Harvey

17. Bicycle: Macmillan

18. Wireless Telegraphy: Signor Marconi

19. Microorganisms: Antoni Van Leeuwenhoek

20. Laser: Dr. C. Gilbert

21. Periodic Table: Mendeleev

22. Radium: Madam Marie Curie

23. Mass/Energy Conversion Equation: Einstein

24. Cement: Joseph Aspdin

25. Simple Microscope: Hans Janssen and Zacharias Janssen

26. Sulphuric, Nitric and Hydrochloric Acid: Jabir Bin Hayan

27. Jet Engine: Frank Whittle

28. Electricity: Thomas Edison

29. Computer: Charles Babbage

30. Lightening Conductor: Benjamin Franklin

31. Semiconductor: Bardeen and Brattain

32. Uncertainty Principle: Heisenberg

33. Cyclotron: Ernest Lawrence

34. Electro Magnetic Engine: James Maxwell

35. Internal Combustion Engine: Nikolas August Otto

36. Earth As A Huge Magnet: William Gilbert

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37. First Person To Orbit Earth: Yuri Gagarin

38. Water: Henry Cavendish

39. Gravitation: Newton

40. Magnet: Dr. Gilbert

41. E.M Induction: Faraday

42. Energy Quanta: Max Planck

43. Vitamin. C Therapy: Linus Pauling

44. First Clone Of A Sheep: Ian Wilmit

45. Streptomycin: S.A.Waksman

46. Helical Structure Of Protein: Linus Pauling

47. Polio Vaccine: Jonas Salk

48. Nylon: Wallace. H Carothers

49. Radioactivity: Becquerel

50. Safety Match: John Walker

51. Gun Powder: Roger Bacon

52. Jupiter: Galileo

53. Neutron: James Chadwick

54. Earth‘s Radius: Eratosthenes

55. Oxygen: Joseph Priestley

56. Noble Gases: Cavendish

57. Synthesis Of Gene In Laboratory: Hargobind Khorana

58. Earth Revolves Round The Sun: Copernicus

59. Binomial Nomenclature: Carl Von Linnaeus

60. North America: Christopher Columbus

61. Green Land: Robert Peary

62. Transistor: William Bradford Shockley

63. Typewriter: Sholes

64. Bacteriology: Pasteur

65. Laser: Theodore Maiman

66. Father Of Botany: Theophrastus

67. Father Of Zoology: Aristotle

68. Father Of Taxonomy: Carolus Linnaeus

69. Father Of Genetics: Gregor Mendel

70. Cell Theory: Scheilden And Schwann

71. Cholera Bacillus: Robert Koch

72. Theory Of Relativity And Photoelectric Effect: Einstein

73. Insulin: Dr. F.G Banting

74. Nucleus: Robert Brown

75. Chromosome: Waldeyer

76. Ultra Violet Rays: Johann Wilhelm Ritter

77. Law Of Attraction And Repulsion Between Electric Charges: Coulomb

78. Battery: Alessandro Volta

79. Electromagnetic theory: James Clerk Maxwell

80. First Person To Televise Pictures Of Moving Objects: John Logie Baird

81. Antiseptic Medicine: Joseph Lister

82. Cotton Gin: Eli Whitney

83. Big Bang Theory: Georges Lemaitre

84. Electron: J.J Thomson

85. Aeroplane: Wilbur and Orville Wright

86. Steam Railway Locomotive: Richard Trevithick

87. Radio: Marconi

88. Household Vacuum Cleaner: Herbert Cecil Booth

89. Bakelite: Baekeland

90. Windscreen Wipers: Marry Anderson

91. Ballpoint pen: Laszlo And Georg Biro

92. Helicopter: Igor Sikorsky

93. DDT: Paul Muller

94. Blood Banking: Charles Drew

95. AK-47: Mikhail Kalashnikov

96. Integrated Circuit: Robert Noyce

97. Cellular Phone: Dr. Martin Cooper

98. Vitamins: Funk 99. Uranus: Herschel

100. Calculating Machine: Blaise Pascal

101. Tuberculosis: Robert Koch

102. Logarithm Table: John Napier

103. Malaria Parasite: Ronald Ross

104. Zero: Al Khwarizmi

105. Velocity Of Light: Roomer

4. Measuring Tools

1. Pressure: Barometer

2. Voltage: Voltmeter

3. Purity Of Milk: Lactometer

4. Temperature: Thermometer

5. Velocity Of Wind: Anemometer

6. Earthquake: Richter Scale

7. Degree Of Humidity: Hygrometer

8. Blood Pressure: Sphygmomanometer

9. Radioactivity: Geiger Counter

10. High Temperature: Pyrometer

11. Rainfall: Rain Guage

12. Earthquake Recording: Seismograph

13. Electric current: Ammeter

14. Altitude: Altimeter

15. Velocity And Direction Of Wind: Anemometer

16. Sensitivity Of Skin: Algeismeter

17.AtmosphericPressure: Aneriodograph/Barometer

18. Improvement Of Hearing Power: Audiometer

19. Quantity Of Heat: Calorimeter

20. Intensities Of Colours: Colorimeter

21. Longitude Of Vessel Over Sea: Chronometer

22. Detection Of Electric Charge: Electroscope

23. Voltage Difference: Electrometer

24. Depth Of The Ocean: Fathometer

25. Small Electric Current: Galvanometer

26. Relative Density of Liquids: Hydrometer

27. Change In Atmospheric Humidity: Hygroscope

28. Detection And Measurement Of Light: Photoelectric Cell

29. Salinity Of Water: Salinometer

30. Spectrum Analysis: Spectroscope

31. Hearing Of Heartbeat And Lung Sound: Stethoscope

32. Maintenance Of A Constant Temperature: Thermostat

33. Amplification Of Current: Transistor

34. Measurement OF Potential Difference Between Two Points: Voltammeter

35. Flow Of Air: Aerometer

36. Radiant Energy: Radiometer

37. Conversion Of Rays Into Mechanical energy: Radiograph

38. Measurement Of Intensity Of Light: Lucimeter

1. The energy of food is measured in Calories

2. The microscope is used to study Small and near objects

3. The S.I unit of temperature is Kelvin

4. The telescope is used for viewing Distant Objects

5. Decibel is a unit of Sound

6. The instrument used to measure Electric Current is Ammeter

7. The apparatus used in submarines to give a clear view of the object, on the surface of the ocean or

ground is known as Periscope

8. Richter Scale is used for measuring Intensity Of Earthquake

9. Fathometer is used to measure Ocean Depth

10. Hygrometer is used to measure Relative Humidity

11. Venturi Tube is used for Measuring Flow Of A Fluid

12. Coronagraph is used for Observing and often photographing the sun‘s corona

13. Microphone is used to convert sound waves into electric energy

14. Velocity of wind is measured by Anemometer

15. Altimeter is used to measure the approximate height above the ground

16. Light year is related to Distance

17. Pressure of gases is measured by Barometer

18. Altitude of the Sun is measured by Sextant

19. There are 981 Dynes in one gram weight

20. When listening to heart beat with stethoscope, one hears closing of valves

21. The unit of Current is Ampere

22. The unit of energy in MKS system is Joule

23. The intensity of an earthquake is measured by Seismograph

24. Centigrade and Fahrenheit scales give the same reading at -40 Degree

25. The instrument, which is used to measure temperature by radiation, is called Pyrometer

26. Centrifuge is used to separate mixtures of chemicals

27. Radio Telescope is used to receive radio waves from objects in space

28. Audiometer is used to measure intensity of sound

29. A chronometer is used to measure time

30. Electroscope detects the presence of electric current

31. Stroboscope is used to view rapidly moving objects

32. Taceometer is used to measure distance, elevations and bearings during survey

33. Retinoscope is an instrument used to determine Refractive power of lens

34. The final image produced by a simple microscope is Virtual and Erect

35. Photodiode is used for the detection of Light

36. A Polaroid is a device used for analysing polarized light

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37. The spectrum of luminous bodies is studied by Spectrometer

38. Transformer is used for conversion of low voltage into high voltage and vice-versa

39. Ophthalmoscope is used to observe Retina

40. Sonar works on the principle of Absorption of sound

5. Everyday Science MCQS Material

1. When the resultant of all the forces acting on a body is zero the body is said to be in a state

of Equilibrium.

2. Gamma Rays are similar to X-Rays.

3. The Separation of ordinary light into its constituent colours is known as Dispersion.

4. If a body weighs 600 kg on the surface of the earth then the weight of the same body on the surface

of moon will be 1/6th i.e. 100kg.

5. When a bullet penetrates into a target, the kinetic energy of a bullet is converted into Mechanical

Energy.

6. The process of digestion begins in Mouth.

7. Sometimes when white blood corpuscles greatly increase in number, they cause a disease

called Leukaemia.

8. The principle of wireless telegraphy was discovered by Signor Marconi.

9. The planet nearest to sun is Mercury.

10. Pressure cooker works on the principle that the boiling point of a liquid increases with the

increase of pressure.

11. Copper is the best conductor of electricity.

12. Blood cells are manufactured by bone marrow of the body.

13. The smallest organism which causes disease is virus and even smaller is called viroids.

14. Neutron, electron and Proton have neutral, negative and positive charges respectively.

15. Of all the flying machines that man has made only Rockets are suitable for space flight.

16. Transistors do not need a warm up period because they have no Filaments.

17. If an object gives off its own light, it is said to be Luminous.

18. An electric heater would be most likely to produce I.R Radiations.

19. The Kelvin scale of temperature is called the absolute scale.

20. The type of radiation that is unaffected by magnetic field is called Gamma Rays.

21. If we know the mass of an object and the force applied on it, it is possible to

calculate acceleration of the object.

22. Active transport in animals and plants required metabolic energy and Concentration Gradient to

carry the substances across cell membrane electrical gradient.

23. Diseases that spread through air are called Air Borne diseases.

24. When iron is less in body, the quantity of Haemoglobin in cell decreases.

25. Arteries become hard due to deposition of Fats and Cholesterol in them.

26. The science of study of old age is called Gerontology.

27. The instrument used for measuring the velocity is called Anemometer.

28. The science which deals with the bird is called Ornithology.

29. The function of the thermostat in a refrigerator is to maintain temperature.

30. Blotting paper absorbs ink because the action of capillary.

31. Mirage is an example of Reflection of Light.

32. The age of a tree can be determined by counting Rings of stem.

33. In a normal resting man, the rate of heart beat is 72 per minute.

34. In Pakistan copper is found in Saindak.

35. American space shuttle Mercury Atlas-6 is the first winged space ship to orbit and return to

airport landing.

36. Myopia is a defect of vision which does not permit to see clearly the distant objects.

37. The brightest planet is Venus.

38. Urea s not a phosphorous fertilizer.

39. Ibn Baitar was a renowned Muslim Botanist.

40. Cellulose is natural polymer.

41. Vitamin A & D are not water soluble.

42. Amoeba is a unicellular animal.

43. Solar eclipse occurs in full moon.

44. Leprosy is a disorder of the Nervous System.

45. Chlorofluorocarbons (CFCs) cause decomposition of ozone.

46. Quartz is chemically a Silicate or Silicon dioxide.

47. Chicken egg is composed of One Cell.

48. Visible light energy has the wave length range of 400-700 nm.

49. The particle with positive charge but having mass equal to that of electron is called Positron.

50. Gas in children‘s play-balloons going upward is hydrogen.

51. Standard pressure is 760 mm-Hg.

52. Iron corrodes due to the formation of Iron Oxide.

53. Starch is a polymer of Glucose.

54. Adrenalin is secreted by the Adrenal Gland.

55. Mars planet is nearest to the earth.

56. The process of conversion of a material from solid state directly to gaseous state is

called Sublimation.

57. Bacteria are parasite.

58. Ruby is an oxide of Aluminium.

59. In the Australian continent nights are larger than days in June.

60. Gypsum is not hydrated calcium carbonate.

61. Uranus is the coldest planet.

62. Chromite ore contains chromium oxide.

63. Mica is a non-conductor of electricity.

64. Sun is not the biggest star in the universe.

65. The capacity to do work is called energy.

66. The energy possessed by body due to its position is called potential energy.

67. Kitab-al-Manazar is publication by a famous Muslim Scientist about Optics.

68. Nucleus usually lies in the centre of animal cells.

69. Calcium and phosphorous are the essential elements of bones.

70. Proteins are formed by combination of amino acids.

71. Rain water dissolves Sulphur dioxide to form Sulphuric Acid.

72. The set of instruction given to a computer is called command.

73. Chemicals such as penicillin which act on bacteria are called antibiotics.

74. Comet shoemaker-levy 9 hit the planet Jupiter in July this year.

75. A branch of medicine studying blood and its disorders is called Haematology.

76. Cytology is the branch of biology which deals with the study of structure and function of cells.

77. A biological study of external form and structure of living organisms or their parts

is Morphology.

78. Am academic and applied discipline which involves the scientific study of human or animal

mental functions and behaviours is called Psychology.

79. A study of the chemical composition of the earth‘s crust is called Geology.

80. In a heat engine heat energy is changed into Mechanical Energy.

81. Frequency of audible sound is 20-20,000 Hz.

82. Deficiency of vitamin B causes Beriberi.

83. Cheapest source of producing electricity is Water.

84. The smallest unit of measurement of wave-length is Angstrom.

85. The chemical generally used in refrigerator is Freon.

86. The unit ―TON‖ to specify air conditioners is equivalent to 12,000 BTU/hour.

87. Unit of electricity ―Kilowatt Hour‖ is the unit of Power.

88. Period of famous Muslim scientists is 7th to 13th century A.D.

89. Heat radiation travels at a speed equal to Speed of light.

90. Cryptograms are non-flowering plants.

91. Reserve food material is usually stored as Starch in plants and Glycogen in animals.

92. Streptococcus is a gram positive bacterium.

93. Spinach is a good source of vitamin K.

94. Insulin is a hormone secreted by the pancreas.

95. Femur is a bone of the leg. 96. The moon has no atmosphere.

97. Excessive burning of the fossil fuels causes acid rains.

98. Twenty first of June is the longest day of the year in the northern hemisphere.

99. Electricity is a secondary source of energy.

100. The outer most layer of the earth is called Crust.

101. Newton is the unit of Force.

102. Radium was discovered by Madam Marie Curie.

103. The memory of the computer is expressed in bytes

104. AIDS is caused by Human Immunodeficiency Virus (HIV).

105. Chemical name of gypsum is Calcium Sulphate.

106. Molten super-hot material present inside a volcano is called Magma/Lava.

107. Richter scale measures the severity of Earthquake.

108. pH of blood is 7.3-7.4.

109. one of the countries through which equator passes is Kenya.

110. Purest form of iron is Wrought Iron.

111. Hypo is a solution of sodium thiosulphate.

112. Cod liver oil contains Vitamin D.

113. Aorta is a n organ of the Circulatory System.

114. Planet Mars has two moons.

115. Bauxite is an ore of Aluminium.

116. Circular aperture which appears as a dark spot in the eyes is called pupil.

117. The speed of light is nearly 300, 0000 km/sec.

118. Ideally water can be used as a car fuel after electrolysis.

119. Our eye is very sensitive to blue light.

120. Al Beruni died in 1048 A.D.

121. Abu ail Sina born in Iraq.

122. Blue colour has shortest wavelength.

123. Light travels fattest in Vacuum.

124. The universe is Expanding.

125. The disease, Haemophilia is caused by the deficiency of Vitamin K.

126. Protein is a nautral polymer.

127. Astronomers cannot be nominated for the Noble Prize.

128. A sheet of muscles called Diaphragm separates the chest from the abdomen.

129. In human body, blood clotting factor is produced by the platelets.

Human blood is able to carry large amounts of oxygen because of the Haemoglobin.

130. The living part of a plant cell is composed of a nucleus and cytoplasm.

131. The pattern for building protein molecule is stored in the messenger RNA.

132. Anvil and stirrup are names of bones present in the ear.

133. The front of the eye is covered with a tough transparent material called Cornea.

134. The young plant inside a grain of wheat is called the Embryo.

135. Inborn behaviour that involves only one part of the body is called Reflex Action.

136. The smallest branches of an artery lead into tiny blood vessels called capillaries.

137. Eustachian tube belongs to ear.

138. Cartilage is a connective tissue.

139. Auricle is present in heart.

140. Tendon is a muscle.

141. Dendrites are the part of Neuron.

142. In an animal cell protein is synthesized in the Ribosome.

143. Chemically finger nails are made up of protein.

144. Muscle stiffness is symptom caused by the disease Tetanus.

145. Riboflavin (vitamin B2) is not affected by cooking.

146. Thiamine is vitamin B1.

147. Ascorbic acid is vitamin C.

148. Rickets is caused by the deficiency of vitamin D.

149. The number of chromosomes in the spermatozoon is 23.

150. The fat in our food is digested by the Enzyme Lipase.

151. The most abundant element in the human body is Oxygen.

152. Sound is a form of energy.

153. A fraction of sunlight is refracted as it enters the earth‘s atmosphere.

154. Rainbows are produced by the reflection of light through rain drops.

155. Light switches in our homes are connected in parallel series.

156. Generators convert mechanical energy into electricity.

157. Modern incandescent bulbs do not contain filaments made of copper.

158. Trout is not a sea fish.

159. Epiphytes are a plant that grows upon another plant.

160. Hepatitis is the inflammation of liver.

161. Meningitis is inflammation of membrane surrounding the brain.

162. Equinox is the time when the sun appears vertically overhead at noon at the equator.

163. Joseph Aspdin is the inventor of cement.

164. Neurology is the science of Nervous system.

165. Biometry is the application of statistics in the study of Biology.

166. Aviculture is the rearing and breeding of birds.

167. Malaria is caused by Plasmodium.

168. Goitre is caused due to deficiency of Iodine in diet.

169. Typhoid is caused by Salmonella Typhosa.

170. Black hole is a hypothetical region of space having a gravitational pull so great that no mater or

radiation can escape from it.

171. Fungicide is used against moulds and fungi.

172. The science which deals with heredity is known as Genetics.

173. Insulin is used for the treatment of Diabetes.

174. Yuri Gagarin is the first space man.

175. The distance between the earth and the sun is called Astronomical unit.

176. The study of chemical processes in living organisms is called Biochemistry.

177. The first computer virus invented by two Pakistani brothers is called the brain virus.

178. Severe deficiency of vitamin C results in Scurvy.

179. Plant cells manufacture their food due to the presence of chlorophyll.

180. Mitosis is a type of cell division where in the number of chromosomes in the daughter cell arethe same.

181. Blood cells are of three types.

182. The ultraviolet rays cause sunburn.

183. Xylem and Phloem are conducting tissues.

184. Carbohydrates are cheapest and most ready source of energy.

185. Enzymes are responsible for chemical digestion of food.

186. Plasma is the fluid part of the blood in which the cells are suspended.

187. Haemoglobin combines with oxygen and transport to different cells of the body.

188. Neutron is the negative charged particle in an atom.

189. Hydrogen is the lightest gas.

190. Mercury is the smallest planet of the solar system.

191. Image of the object is formed on the retina of the eye.

192. Barometer is used for measuring the pressure.

193. Monomer of proteins is Amino Acids.

194. Water transport in plants occurs within Xylem.

195. Underground horizontal stems are allied Rhizomes.

196. In the eye only Retina contains receptors for light energy.

197. Plant Hormones control plant response to environment stimuli.

198. Mitochondria are often called the powerhouse of the cell.

199. The rate at which a current changes direction is called its Line Frequency/Main frequency.

200. Diamond is an allotropic form of the element Carbon.

201. Speed of the wind is measured by Anemometer.

202. Ligament connects the muscle with the bone.

203. Polio is caused by virus.

204. Neptune is the coldest planet of the solar system.

205. Eggshell is composed of calcium carbonate.

206. The most abundant element in the earth‘s crust is oxygen.

207. The main constituent of Biogas is Methane.

208. Stalagmites are deposits of Calcium Carbonate.

209. Gigantism is the result of Hyper Pituitarism.

210. The purpose of computer is Manipulation of data.

211. The chemical name of washing soda is Sodium Bicarbonate.

212. The main constituent of Sui gas is Methane.

213. Blue colour has the shortest wave length.

214. Glass is called Silica.

215. Ascorbic Acid is Vitamin C.

216. The solar system has 8 planets.

217. The second most abundant element in the earth‘s crust is silicon.

218. The fastest revolving planet is Mercury.

219. Geysers are hot springs that erupt hot waters and steam from time to time.

220. The first simple microscope was invented by Hans Janssen and Zachariah Janssen.

221. Hot liquid rock beneath the earth‘s surface is called Lava/Magma.

222. Mitochondria are the power house of the cell.

223. Ability of the air to absorb long heat waves from the earth after allowing the short waves from sun to pass through it is known as Green House Effect.

224. Computer works on the principle introduced by the Muslim scientist Musa al-Khwarizmi.

225. Coldest planet of the solar system is Neptune.

226. The rupture of red blood cells is called Eryptosis.

227. Muslim Scientist Ail bin Tabari is famous for his work on Firdous al-Hikmah.

228. Haploid cells result from the process of meiosis.

229. All stars are not of the same colour.

230. The left lung has two lobes while the right lung has three lobes.

231. The pulmonary veins return oxygenated blood to the right atrium.

232. Our galaxy milky way is shaped like a large thick concave lens with a large central bulge

233. DNA has a double helix structure while the RNA does not have a double helix structure.

234. The normal temperature of Human Blood is 37C (98.60 F)

235. The liver is a part of gastrointestinal tract.

236. The major fossil fuel impurity is Sulphur.

237. Sphalerite is an ore of Zinc.

238. The most abundant element present in the sun is Hydrogen.

239. The metal atom present in chlorophyll is Magnesium.

240. The gland responsible for the secretion of the hormone estrogen is Ovary.

241. An element used in the doping of silicon for the preparation of a p-type semiconductor is Boron.

242. A synthetic fibre which is a polyamide is Nylon.

243. Glycogen is a carbohydrate.

244. The cell structure that controls movements of material into and out of the cell is Cell Membrane.

245. The unit that co-ordinates different devices of the computer system are Control Unit.

246. Mastication is an example of Mechanical Digestion.

247. Botanically a fruit is a Ripened Ovary.

248. The vocal folds are part of the Larynx.

249. The famous book Al-Qanoon was written by the Muslim scientist Abu Ail Sina.

250. The instrument used for the measurement of blood pressure is Sphygmomanometer.

251. A mammal, which can fly is Bat.

252. A disease which is more common in men than in women and is hereditary in character is Colour

Blindness.

253. Snow Leopard is an endangered animal species of Pakistan.

254. Cinnabar is an ore of Mercury.

255. Anabaena azolla is cyanobacterium.

256. The nuclear reaction taking place on the surface of sun is Nuclear Fusion reaction.

257. Jabir bin Hayan prepared Sulphuric Acid.

258. The constituent elements of Brass are Copper and Zinc.

259. The conversion of non-diffusible substances into diffusible ones by the action of enzymes is

called digestion.

260. Diamond is the purest naturally occurring crystalline form of Carbon.

261. Caustic soda is extensively used for making Soap.

262. When a person can see nearer objects but not the distant ones he is said to be suffering

from Myopia/Near-sightedness/Short sightedness.

263. Marble is a metamorphic rock.

264. Curie is a unit of Radioactivity

265. The brown colour of rust is because of Oxidation of iron/formation of iron oxide.

266. The movement of food through oesophagus is by the muscular action is known as Peristalsis.

267. Granite is a form of igneous rock.

268. Cellulose is the min chemical substance in the plant cell wall.

269. Cell Nucleus was first discovered by Robert Brown.

270. Enzymes are organic catalysts made up of proteins.

271. Animals obtain carbohydrate mainly from Starch.

272. The minimum speed of a Pentium II computer is 233 MHz

273. According to recent classifications the living organisms are divided into 5 kingdoms.

274. Glycolysis is a process of Respiration.

275. The unit that coordinates different devices of Computer system is control Unit.

276. Seed is technically Ripened Ovule.

277. ADH is a hormone secreted by Posterior pituitary gland.

278. Permian Period belongs to Palaeozoic era.

279. Right kidney in man is slightly lower in position than the left kidney.

280. Light is visible.

281. Steel is more elastic than rubber.

282. Pitch of man‘s voice is lesser than that of woman.

283. Diastolic blood pressure is lesser than systolic blood pressure.

284. Guava contains more vitamin C than orange.

285. A light year is a unit of distance.

286. Mercury is heavier than lead.

287. Kangaroo Rat is a desert mammal which does not drink water.

288. Aqua Regia is a mixture which can dissolve platinum.

289. The constituent elements of Bronze are tin and copper.

290. The deficiency of Thiamine (B1) causes Beriberi.

291. A nuclear reaction in which two or more than two lighter nucleus are fused together to form arelatively heavier one is called Nuclear Fusion.

292. Diamond is the purest naturally occurring crystalline form of carbon.

293. The hormone secreted by adrenal cortex is Corticosteroids (Cortisol & aldosterone)

294. The three colours combination which produces the sensation of white light is Red, Green andBlue.

295. A six feet tall lady can see her full image in a three feet plane Mirror.

296. Vanadium, a steel gray corrosion resistant metal occur naturally in oxide state.

297. Fibre optics cable carries data in the form of light.

298. Blue flame is hotter than red flame.

299. The falling of yellow leaves during autumn is the seasonal time for plants to get rid of

accumulated wastes.

300. Friction is necessary evil.

301. Cancer can be treated by Chemotherapy and Radiotherapy.

302. The velocity of a moving object is least where the pressure is greater.

303. The largest planet of solar system is Jupiter.

304. The temperature of the dead human body on Celsius scale is 25C (Normally room Temperature)

305. The number of the spinal nerves in the man is 31 pairs.

306. A primary cell cannot be charged again.

307. Halos around the moon are formed because of the phenomenon of dispersion.

308. Muscle stiffness is called by a disease called Tetanus.

309. Oil rises in a wick of oil lamp on account of a property of matter called Capillary action.

310. Muslim scientist Ail al Tabari is famous for his work on Firdous al-Hikmah.

311. The three elements needed for healthy growth of plants are N (nitrogen), P (phosphorus) and K(potassium).

312. Ammonium nitrate is not used for rice crop.

313. Sea divers use a mixture of gases for breathing during diving. The mixture is 80% He & 20%O2.

314. Ascorbic acid is a water soluble vitamin.

315. Lipase enzyme brings about hydrolysis of fats.

316. The solution if benzoic acid is used for seasoning of food.

317. Influenza is caused by virus.

318. The energy possesses by water in a dam is potential energy.

319. The organ in the human body which is responsible for the digestion of protein only is stomach.

320. Nicolas Leonard Sadi Carnot designed the first internal combustion engine used to burn low

grade fuel.

321. William Gilbert was the scientist who asserted the earth to be a huge magnet.

322. The metal known as quick silver is called Mercury.

323. Electrochemical cell converts the chemical energy into electrical energy.

324. Yuri Gagarin was the first person to orbit the earth.

325. Water was discovered by Henry Cavendish.

326. To say in the sunlight while circling the globe at the equator, one has to move with a speed

of 1670 km/hour.

327. Infrared waves have more wavelengths than the red colour.

328. Liver produces bile which is involved in the breakdown of fats.

329. A secondary cell can be charged again.

330. The study of human population is called Demography.

331. Human being belongs to species called Sapiens.

332. Defect of eye due to which nearly located objects are not clearly visible is

called Hyperopia/Hypermetropia.

333. About 60-70% of the human body consists of water.

334. All of the oxygen that we breathe has been produces by the splitting of water

during Photosynthesis.

335. The important ore of Chromium is Chromite.

336. The measurement of rainfall is made by an instrument known as Rain gauge.

337. Oxidation means loss of electron.

338. Poplar is woody raw material which is used for the manufacture of paper pulp.

339. Rectified spirit contains alcohol about 95%.

340. The Famous book; Al-Qanoon was written by the Muslim scientist Abu Ail Sina

341. Basic metals can be converted into gold by artificial nuclear radioactivity.

342. One of the main functions of the earth‘s ozone layer is to filter out ultraviolet rays.

343. The alloy consisting of metals copper, zinc and nickel is called Paktong/Alpaca/Nickel

Silver/German Silver

344. The instrument specially designed for recording earthquake waves is called Seismograph.

345. The electrical device which converts sound energy into electrical energy is Microphone.

346. The ore of mercury metal is Cinnabar.

347. The variation of blood flow can be heard thorough Sphygmomanometer.

348. Alexander Fleming discovered penicillin.

349. Neil Armstrong was the first astronaut who first landed on the surface of the moon.

350. Kangaroo rat is the desert mammal which does not drink water.

351. Heat transfers from the sun to the earth through Radiation.

352. Pitch of the cat sound is greater than the dog sound.

353. Ultraviolet light is not visible.

354. A guava contains more vitamin C than an orange.

355. Sound travels faster in iron than air.

356. Wheat Bridge is the name of an electrical circuit.

357. Morphine can cause constipation and lowering of blood pressure.

358. A convex lens is used for the correction of the Hyper-phobia.

359. The nucleic acids are responsible for proteins synthesis in the human body.

360. Entomology is the branch of zoology which deals with the study of insects.

361. Beri Beri is the disease which is caused by the deficiency of vitamin B1.

362. Oil rises in a wick of oil lamp because of a property of matter, called Capillary action.

363. The production of genetically identical offspring is called as Cloning.

364. Mercury is the fastest planet of the solar system.

365. Mercury metal is 13.5 times heavier than water.

366. Relative density of milk is measured by an instrument known as Lactometer.

367. The temperature of a human body is measured by an instrument known as Mercury

thermometer.

368. Gold and silver are known as coinage metals.

369. The amount of ozone in the atmosphere is expressed in ppm (parts per million).

370. One of the country through which equator passes is Kenya

371. Max Planck received the Noble prize in Physics in 1918 for his discovery of energy quanta.

372. Bronze is made up of copper and tin

373. Addison‘s disease is caused by the excessive secretion of Adrenocorticotrophic Hormone.

374. Margalla Hill is a branch of Himalaya Range

375. Humming bird belongs to a category called Endotherm

376. Insulin is secreted by Pancreas, thyroxin by Thyroid gland, Adrenalin by Adrenal gland,

Oestrogen by Ovary, cortisol by Adrenal gland, Testosterone by Testes of male and ovaries of female

377. Japan is called Land of rising sun.

378. Rodenticides are used to kill rats.

379. Venus planet of our solar system is called as Morning Star.

380. The diameter of the earth is 12742 km.

381. Insects are invertebrates

382. Opium is found in poppy.

383. Opium is used to make Heroine.

384. Kitab-al-Manadhir was written by Ibn-al-Haisham.

385. Speed of light is 300000 km/sec

386. Generators convert mechanical energy into electric energy.

387. Dry ice is CO2.

388. Telephone was invented by Dr. Graham Bell.

389. Ammeter is the instrument which is used to measure electric current.

390. Ascorbic acid is vitamin C.

391. Total number of bones in human face is 14.

392. The sky appears blue due to Tyndall Effect.

393. A, D, E, K are fat soluble vitamins

394. The composition of the mixture used for welding is Copper Oxide and Aluminium.

395. Abu ail Sina, Al Beruni, Ibn Al Haisham belonged to which 10th century.

396. Bakelite is not a Thermoplastic.

397. Haematite (a mineral) is the important source of iron.

398. Bauxite is the mineral of Aluminium.

399. Bronze is an alloy of copper and tin.

400. Skin is the largest organ of the body.

401. Vaccine for T.B is Bacillus Calmette Guerin (BCG)

402. Mitochondria is called the power house of the cell.

403. Persons with AB+ blood group are considered to be universal recipient.

404. Study of life in outer space is known as Exobiology.

405. The name of the common mineral salt present in sweat is Sodium Chloride.

406. Sensitive layer of the eye is Retina.

407. Laughing gas as the composition of Nitrogen and Oxygen.

408. Dr. Abdus Salam of Pakistan was one of the contributors of the unification of Electromagnetic

force and weak nuclear force.

409. CAT triplet in DNA codes for valine.

410. The chance of diabetic baby born to parents both heterozygous normal is ¼.

411. Inheritance of acquired characters is not an art of Darwinism.

412. Role of biotechnology in the production of food is based on Fermentation.

413. Founder of modern astronomy was Nicolas Copernicus.

414. The instrument which measures very high temperature is Pyrometer.

415. The science which deals with study of manners and customs of people is Ethics.

416. Dry ice is Solid Carbon Dioxide.

417. Chemical name of vinegar is Dilute Acetic Acid.

418. Deficiency of Pyridoxine decreases haemoglobin production.

419. Orbital period of the planet Mercury around the sun is 88 days.

420. The most splendid and the most magnificent constellation on the sky is Orion.

421. ―Black holes‖ refer to Collapsing objects of high density.

422. Eugenics is the study of altering human beings by changing their genetic components.

423. The position of earth in its orbit when it is at its greatest distance from the sun causing northern

summer is called Aphelion.

424. Ionosphere layer make the radio transmission possible.

425. Television signals are converted into light signals by Transistor.

426. Most of Asteroids lie in asteroid belt between the orbit of Mars and Jupiter.

427. The number of spark plugs needed in a diesel engine is 0.

428. The half-life of a radioactive element is 8 days. It takes 8 days to reduce it from 10mg to 5 mg.

429. The term ―Blue Shift‖ is used to indicate Doppler Effect in which an object appears bluer when

it is moving towards the observer or observer is moving toward the object.

430. Kilowatt-hour is a unit of Power.

431. Fuel used in a Fast Breeder Reactor is Uranium Plutonium Oxide.

432. Monsoon is caused by Revolution of earth.

433. Atmospheric layer ionosphere helps in radio communication.

434. A moderator is used in nuclear reactor in order to slow down the speed of the neutrons.

435. Sedimentary rocks are Porous.

436. Gypsum is a non-metallic mineral.

437. Ozone layer prevents the ultraviolet radiation from entering the atmosphere.

438. The phenomenon of Aurora Borealis, the display of red and green lights in northern hemisphere

is due to radiations from Ionosphere.

439. Oasis is associated with Desert.

440. Quartz crystal in quartz watches work on the principle called Piezo-electric effect.

441. The fruits with seed, like banana, are called Parthenocarpic fruits.

442. Animal which captures and readily kills living animals for tis food is called Predator.

443. In a railway track, two rails are joined end in end with a gap in between them to avoid accidents

due to expansion.

444. Al-Qanoon is the famous book of Ibn-e-Sina in which human physiology and medicine are

discussed.

445. Copper can be converted into gold by Artificial Radioactivity.

446. In winter an iron pipe feel colder than a wooden window. This is because wood is nonconductor.

447. The echo (reflected sound) will be distinctly heard only at ordinary temperatures if the distance

of the reflecting surfaces from the source of sound is at least 56 ft.

448. It is possible to recognize a person in the dark by simply hearing hiss unique voice. It is because

of the Pitch.

449. When a ray of sunlight enters a dark room, its straight path becomes visible because of dust

particles hanging in the air. It is because light is Transparent.

450. The principle used in radar is the same as that of sonar. In radar we use radio waves; whereas in

sonar we use Ultrasonic.

451. Parsec is a unit of distance.

452. The German or nickel silver is composed of approximately 60% copper, 20% nickel and 20%

zinc.

453. The temperature of the dead body is the temperature of the place where it is kept.

454. Cusec is the unit for measuring the flow of liquids/flow rate, equal to one cubic foot per second.

455. The deepest place on earth is Mariana trench.

456. Twinkling of stars is caused by Refraction of light.

457. Magnifying power of a simple microscope can be increased by decreasing focal length of the

lens.

458. A very important practical application of properties of matter is hoeing or ―godi‖ practiced by

the farmers. This property of matter is called Capillarity.

459. It is observed that the total pressure exerted by air on the man of average size is around 14.7 lb.

wt. per square inch. But the man feels quite comfortable. It is because of an equal and opposite

pressure acts from inside.

460. A nuclear reactor is a device used to carry out controlled nuclear reaction whereas GM counter

is a device used to detect nuclear radiation.

461. A body can escape the gravitational pull of the earth if it is thrown up with a velocity of 7 miles

per sec.

462. Night vision is possible with the help of Infrared Rays.

463. Myopia is a defect of human eye. It can be corrected by using a lens called concave lens.

464. Walnuts can be broken in the hand by squeezing two together but not one. It is because of work

done.

465. The instrument which is specially designed for recording earth quake wave is called

seismograph which measure earth quake waves on a Richter scale.

466. Fossils found in the lowest geological strata are generally most primitive.

467. Evolution can be described as a continuing process.

468. Mutation is the only source new alleles.

469. Polygenic characteristic are controlled by Multiple Genes.

470. Digestion involves ingestion, digestion, absorption and elimination.

471. In humans, most nutrient molecules are absorbed by the small intestine.

472. The energy needed to fuel essential body processes is called Basal metabolism.

473. Inhaled air passes through Bronchiole in the last.

474. Hermaphroditism is a form of sexual reproduction.

475. Cobalt is a metal which is strongly attracted by a magnet.

476. Hepatitis A is transmitted to different individuals by Faeces.

477. The unit that coordinates different devices of the computer system is Control unit.

478. The approximate intensity level of the sound which can cause damage is 100 decibel (dB).

479. Fuse wire is made of 63% tin and 37% lead.

480. The unit of photosynthesis in green plants is called Quantosome.

481. The property by virtue of which metals can be beaten into thin sheets is known as Malleability.

482. The sky appears blue because the earth‘s atmosphere Reflects blue light.

483. Gamma rays are Higher energy rays emitted by radioactive elements.

484. The radiation that is used in magnetic resonance imaging (MRI) is in the infra-red range.

485. Lead is used in storage batteries.

486. The gas produced during the fermentation of Biomass is Methane.

487. Biogas is the common name of Natural Gas.

488. Bacteria help in the process of fermentation of biomass.

489. One thousand watt power is called as 1 kilowatt.

490. The meter installed in our homes measure electricity in KWh.

491. Unis of electricity consumed by 2500 watt air-conditioner in one hour are 2.5 units.

492. Gas bills are charged in CGS and BTU.

493. In BTU system, one BTU is equal to 1055 joule.

494. Air is present in the atmosphere of earth up to the height of 200 kilometres.

495. All forms of energy that we use are ultimately transformed into Heat energy.

496. The gas which acts as a glass of greenhouse is Carbon dioxide.

497. Google is the largest search engine of internet.

498. Carbon dioxide is used in the preparation of soft drinks.

499. World‘s largest flower auction is held in Aalsmeer.

500. All the plant life is based upon the compounds, which are made up of Oxygen, Carbon and

Nitrogen.

501. Huge white ball in the sun almost consists of Hydrogen.

502. Charcoal is made by heating wood.

503. In blood, the percentage of water is 90%.

504. As the temperature of ice rises, the ice melts and its density increases.

505. Water is a universal solvent for Biochemical Reactions.

506. The temperature of the water below the solid ice layer is 4 degree centigrade.

507. The volume percentage of nitrogen in air is 78%.

508. The composition of oxygen in air is kept constant by the process of Photosynthesis.

509. Nitrogen occurs in plants and animals in the form of Protein.

510. Air contains volume of carbon dioxide approximately 0.03%.

511. The gases which are used by divers as an artificial atmosphere are helium and oxygen.

512. Noble gases are extremely unreactive.

513. The second most abundant metal found in the earth‘s crust is Iron.

514. The iron content in plant tissue is normally between 50-250ppm.

515. Chernobyl nuclear reactor lies in Russia.

516. Chernobyl nuclear plant was destroyed in 1986 due to Failure of cooling system.

517. Radioactive source must be kept in Lead Container.

518 In Brazil alcohol is used as fuel for vehicles.

519. Voltmeter can be made by modification in Galvanometer.

520. The device used for the measurement of current, voltage and resistance is AVO meter.

521. In the name of multimeter ―AVO‖, V stands for Voltage.

522. Silicon is a Semiconductor.

523. Paper is an insulator.

524. For sending sound waves at large distance, Radio Waves are used.

525. The carrier waves used for the radio transmission have the frequency up to 30 KHz.

526.Video camera is used to convert Picture into electrical signals.

527. In a colour television, the colours are green, red and blue.

528. The waves used for sending signals to the satellite from ground station are Micro Waves.

529. First telegraph signal was transmitted in 1901.

530. In a telephone receiver, Magnet is placed under the diaphragm.

531. Nowadays, the international communication and transmission is being done through the waves

known as Microwaves.

532. Modern Bicycle was invented by Staley.

533. Coulomb is the unit of Electric Charge.

534. For certain reasons, some people develop cloudy areas in one or both lenses. This defect is

called Cataract.

535. In order to prevent the corrosion of iron pipes they are often coated with a layer of zinc. This

process is termed asGalvanization.

536. In a reactor, cadmium rods re used for Absorbing Neutrons.

537. Detergents dissolved in water help in cleaning clothes by reducing the surface tension of water.

538. The swing of a spinning cricket ball in the air can be explained on the basis of Bemoulli‘s

Theorem.

539. The absorption of ink by blotting paper involves Capillary Action phenomenon.

540. Materials for rain proof coats and tents owe their water proof properties to Surface Tension.

541. For being able to see three-dimensional pictures we have to use An Epidiascope.

542. Water has maximum density at 4 degree centigrade.

543. The highest recorded air temperature in the world in degree Celsius is 57.

544. The instrument that measures wind speed is the anemometer.

545. The theory of expanding Universe was first propounded by Hubble.

546. Used tea leaves contain Quinine.

547. A lake starts freezing because of the cold atmosphere. It will first freeze at the top surface.

548. The Sun remains visible for some time after it actually sets below the horizon. This happens dueto Atmospheric Refraction.

549. An iceberg is floating in sea. One tenth of its mass will remain above the surface of water.

550. Bat has the highest upper limit of audible range.

551. ―Hotline‖ is A telecommunication link between the rulers of countries.

552. Most of the ozone is concentrated in the Stratosphere.

553. The cow‘s milk contains 80% of water in terms of percentage.

554. Numismatics is the study of Coins.

555. Measles is a viral disease.

556. Vitamin C is present in Citrus Fruits.

557. Leukaemia is a Blood Cancer.

558. Haemophilia is a hereditary disease.

559. Diamond is the hardest material.

560. Lead ball falls through water more slowly than through air because of the viscous force in water.

561. Polaroid‘s are used for Photoelasticity.

562. Scalding with steam is more severe than scalding by boiling water because Steam contains more energy than boiling water.

563. Cooking oil can be converted into vegetable ghee by the process of Hydrogenation.

564. Stainless steel is an alloy of Iron, Chromium and Nickel.

565. Optical fibres work on the principle of Total internal reflection.

566. Water vapour beyond the dew point results in Condensation.

567. The main chemical substance present in the bones and teeth of animals is Calcium Phosphate.

568. The Green House Effect is caused by an excess of Carbon dioxide.

569. Bats can also fly in dark because they are capable of taking the help of Ultrasonic Waves.

570. Gold is found in its original form.

571. Green vegetables have high iron content.

572. The fat content in buffalo milk is 10%.

573. Whale has the largest egg.

574. The rear view mirror of a motor vehicle is Convex.

575. A post mortem study usually involves an analysis of liver.

576. Bio fertilisers are nitrogen-fixing micro-organisms which can enrich soil.

577. Tincture of iodine consists of A solution of iodine in alcohol.

578. The only planet of solar system which has water vapours is Neptune.

579. The major part of natural gas, petroleum and coal consist of Methane.

580. Gypsum is used for cement.

581. Chromium is obtained from Chromite.

582. Silica is used in glass-making.

583. Human population has become double during the last 45 years.

584. At present population growth rate in Pakistan is 1.573%.

585. In Pakistan, the nuclear power stations are built at Karachi and Chashma.

586. Plutonium is used as Fuel for nuclear fission.

587. Uranium-235 is used in the fission process.

588. The solar energy falling on the atmosphere of earth is almost 1.4 kilowatt per square meter.

589. The large plates of solar panels are painted Black.

590. The temperature of the semi-molten rocks about 10 km below the surface is 200 degree

Centigrade.

591. Cataract is a disease of eye.

592. Rayon is made of Cellulose.

593. Meter per second is a unit of Velocity.

594. The greatest number of compounds is formed by the element of Carbon.

595. The major component of honey is Glucose.

596. The working principle of a washing machine is Centrifugation.

597. Oxygen is present in the largest amount in terms of per cent by mass in the earth‘s crust.

598. Radioactivity was first discovered by Henry Becquerel.

599. Helium gas is commonly used in balloons and airships.

600. The process of elimination of water from any system is called Dehydration.

501. Huge white ball in the sun almost consists of Hydrogen.

502. Charcoal is made by heating wood.

503. In blood, the percentage of water is 90%.

504. As the temperature of ice rises, the ice melts and its density increases.

505. Water is a universal solvent for Biochemical Reactions.

506. The temperature of the water below the solid ice layer is 4 degree centigrade.

507. The volume percentage of nitrogen in air is 78%.

508. The composition of oxygen in air is kept constant by the process of Photosynthesis.

509. Nitrogen occurs in plants and animals in the form of Protein.

510. Air contains volume of carbon dioxide approximately 0.03%.

511. The gases which are used by divers as an artificial atmosphere are helium and oxygen.

512. Noble gases are extremely unreactive.

513. The second most abundant metal found in the earth‘s crust is Iron.

514. The iron content in plant tissue is normally between 50-250ppm.

515. Chernobyl nuclear reactor lies in Russia.

516. Chernobyl nuclear plant was destroyed in 1986 due to Failure of cooling system.

517. Radioactive source must be kept in Lead Container.

518. In Brazil alcohol is used as fuel for vehicles.

519. Voltmeter can be made by modification in Galvanometer.

520. The device used for the measurement of current, voltage and resistance is AVO meter.

521. In the name of multimeter ―AVO‖, V stands for Voltage.

522. Silicon is a Semiconductor.

523. Paper is an insulator.

524. For sending sound waves at large distance, Radio Waves are used.

525. The carrier waves used for the radio transmission have the frequency up to 30 KHz.

526. Video camera is used to convert Picture into electrical signals.

527. In a colour television, the colours are green, red and blue.

528. The waves used for sending signals to the satellite from ground station are Micro Waves.

529. First telegraph signal was transmitted in 1901.

 

530. In a telephone receiver, Magnet is placed under the diaphragm.

531. Nowadays, the international communication and transmission is being done through the waves

known as Microwaves.

532. Modern Bicycle was invented by Staley.

533. Coulomb is the unit of Electric Charge.

534. For certain reasons, some people develop cloudy areas in one or both lenses. This defect is

called Cataract.

535. In order to prevent the corrosion of iron pipes they are often coated with a layer of zinc. This

process is termed asGalvanization.

536. In a reactor, cadmium rods re used for Absorbing Neutrons.

537. Detergents dissolved in water help in cleaning clothes by reducing the surface tension of water.

538. The swing of a spinning cricket ball in the air can be explained on the basis of Bemoulli‘s

Theorem.

539. The absorption of ink by blotting paper involves Capillary Action phenomenon.

540. Materials for rain proof coats and tents owe their water proof properties to Surface Tension.

541. For being able to see three-dimensional pictures we have to use An Epidiascope.

542. Water has maximum density at 4 degree centigrade.

543. The highest recorded air temperature in the world in degree Celsius is 57.

544. The instrument that measures wind speed is the anemometer.

545. The theory of expanding Universe was first propounded by Hubble.

546. Used tea leaves contain Quinine.

547. A lake starts freezing because of the cold atmosphere. It will first freeze at the top surface.

548. The Sun remains visible for some time after it actually sets below the horizon. This happens due

to Atmospheric Refraction.

549. An iceberg is floating in sea. One tenth of its mass will remain above the surface of water.

550. Bat has the highest upper limit of audible range.

551. ―Hotline‖ is A telecommunication link between the rulers of countries.

552. Most of the ozone is concentrated in the Stratosphere.

553. The cow‘s milk contains 80% of water in terms of percentage.

554. Numismatics is the study of Coins.

555. Measles is a viral disease.

556. Vitamin C is present in Citrus Fruits.

557. Leukaemia is a Blood Cancer.

558. Haemophilia is a hereditary disease.

559. Diamond is the hardest material.

560. Lead ball falls through water more slowly than through air because of the viscous force in water.

561. Polaroid‘s are used for Photoelasticity.

562. Scalding with steam is more severe than scalding by boiling water because Steam contains more

energy than boiling water.

563. Cooking oil can be converted into vegetable ghee by the process of Hydrogenation.

564. Stainless steel is an alloy of Iron, Chromium and Nickel.

565. Optical fibres work on the principle of Total internal reflection.

566. Water vapour beyond the dew point results in Condensation.

567. The main chemical substance present in the bones and teeth of animals is Calcium Phosphate.

568. The Green House Effect is caused by an excess of Carbon dioxide.

569. Bats can also fly in dark because they are capable of taking the help of Ultrasonic Waves.

570. Gold is found in its original form.

571. Green vegetables have high iron content.

572. The fat content in buffalo milk is 10%.

573. Whale has the largest egg.

25

.

.

574. The rear view mirror of a motor vehicle is Convex.

575. A post mortem study usually involves an analysis of liver.

576. Bio fertilisers are nitrogen-fixing micro-organisms which can enrich soil.

577. Tincture of iodine consists of A solution of iodine in alcohol.

578. The only planet of solar system which has water vapours is Neptune.

579. The major part of natural gas, petroleum and coal consist of Methane.

580. Gypsum is used for cement.

581. Chromium is obtained from Chromite.

582. Silica is used in glass-making.

583. Human population has become double during the last 45 years.

584. At present population growth rate in Pakistan is 1.573%.

585. In Pakistan, the nuclear power stations are built at Karachi and Chashma.

586. Plutonium is used as Fuel for nuclear fission.

587. Uranium-235 is used in the fission process.

588. The solar energy falling on the atmosphere of earth is almost 1.4 kilowatt per square meter.

589. The large plates of solar panels are painted Black.

590. The temperature of the semi-molten rocks about 10 km below the surface is 200 degree

Centigrade.

591. Cataract is a disease of eye.

592. Rayon is made of Cellulose.

593. Meter per second is a unit of Velocity.

594. The greatest number of compounds is formed by the element of Carbon.

595. The major component of honey is Glucose.

596. The working principle of a washing machine is Centrifugation.

597. Oxygen is present in the largest amount in terms of per cent by mass in the earth‘s crust.

598. Radioactivity was first discovered by Henry Becquerel.

599. Helium gas is commonly used in balloons and airships.

600. The process of elimination of water from any system is called Dehydration.

601. Sparkling red colour after the blast of fire cracker is due to the presence of Sulphur.

602. The chemical name of aspirin is Acetylsalicylic acid.

603. Animal fat has the highest calories per gram.

604 The commonly present element in the artificial fertilizer is Potassium, Nitrogen and Phosphorus.

605. Potassium nitrate is used in fertilizers.

606. The inherited traits of a person can be investigated by the study of Deoxyribonucleic acid.

607. Silicon is extensively used in electronics.

608. When a bullet is fired upwards vertically, it gains in Potential energy.

609. The mixture of Acetylene and oxygen gases is required in gas welding.

610. Isobars are the lines connecting the places having same Atmospheric pressure.

611. The velocity of wind is related to Pressure gradient.

612. The acid present in the sour milk is Formic acid.

613. The most important stimulant in tea leaves is Caffeine.

614. Dolly was the name of first cloned sheep.

615. The smallest living cell is that of a Mycoplasma (bacterium)

616. We lose consciousness if blood flow to the brain is cut off more than 5 sec.

617. Menopause usually occurs between 40 to 45 years.

618. Platypus and Echidnas are the only monotremes, or mammals that lay eggs.

619. Film is that part of camera which is analogue to the retina in the human eye.

620. 72-80 is the average adult pulse rate.

621. Magnetic resonance is the modern tool for imaging brain tumours.

622. The acid used in a car battery is sulphuric acid.

26

.

.

623. After drinking contaminated water, you would be most apt to develop symptoms of Typhoid

fever.

624. In eye donation, Cornea of donor‘s eye is utilized.

625. Alzheimer is a disease of Brain.

626. Cell was discovered by Robert Hooke.

627. A body is taken from Earth to Moon. Its weight will Decreases.

628. Brass is an alloy of Copper and Zinc.

629. Mineral essential for the coagulation of blood is Magnesium.

630. Milk is an example of Emulsion.

631. Iron is the most abundant transition metal.

632. Hydrometer is used to determine specific gravity of liquids.

633. Convex lenses are used for the correction of Long-sightedness (Hyperopia)

634. A transformer is used to Increase or decrease AC voltage.

635. The stones formed in human kidney consist mostly of Calcium oxalate.

636. Most of the explosions in mines occur due to the mixing of Methane with air.

637. A mobile phone sends and receives messages through Radio waves.

638. Fax machine receives the signal and give its output through the Printer.

639. The procedure of crushing the gallstone and kidney stone by laser is called Lithotripsy.

640. Laser is used to produce an image of One dimension.

641. Three dimensional image formed by laser is called Photograph.

642. The first laser ever used is Semiconductor laser.

643. Ordinary light spreads in all directions.

644. Optical fibres are the fine strands of Glass.

645. The satellites which revolve in such an orbit, so that they move with earth rotation are

called Geo-stationary satellites.

646. The elements which emit radiations have atomic number greater than 82.

647. In a normal healthy body, the number of red cells or erythrocytes in each cubic millimetre of

blood is 5.0 m.

648. The average life of a red blood cell in the body is about 120 days.

649. DNA is a class of nucleic acids.

650. Cellulose is a Carbohydrate.

651. After long periods of use, a gray spot develops on the inside of a bulb. This is because

the tungsten filament evaporates and collects there.

652. Ice cubes are added to a glass of pure water and a glass of a pure alcohol. The ice would

be Floating in alcohol and sinking in water.

653. Protein which renders a cell less susceptible to attack by viruses is called Chloromycetin.

654. The pigment involved in photosynthesis activity is called Chlorophyll.

655. The chemical part of the dye that absorbs light and produces colour is called photo chrome.

656. A nuclear reactor harnesses nuclear energy by Controlled chain reaction.

657. Eyes are tested by dilating the pupils with a very dilute solution of Atropine.

658. Phenol is used as a raw material in the manufacture of foam used in mattresses, cushions, etc.

659. ECG is an instrument used for the disorder of Heart.

660. Carbon-14 is used for dating very old objects of archaeological importance.

661. Lead is used in storage batteries.

662. Enzymes are Biological catalysts.

663. DNA finger-printing is the latest technology used in Forensic science.

664. Potassium is used in the preparation of glass and soap in the form of Carbonates.

665. Potassium phosphate is used in the preparation of detergent.

666. In Chlorophyll, magnesium is present.

667. Calcium plays a vital role in blood clotting.

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.

668. For water purification, Chlorine is used

669. Deficiency of calcium causes the impaired growth in infants.

670. Wheat, rice, corn and maize are the best sources of carbohydrates.

671. The human blood is divided into four groups.

672. The muscles, tissues and blood all are made up of Proteins.

673. Iron is a part of haemoglobin which transports oxygen.

674. In thyroid glands iodine is required for the synthesis of Thyroxin.

675. The amount of calories provided by egg is 150 K calories/100gm.

676. Jupiter is the largest planet of solar system.

677. The mirror placed near the driver of a bus is Concave mirror.

678. X-rays are used to disintegrate bladder stones.

679. The percentage of carbohydrates in the normal daily food calorie requirement of an adult is

about 59%.

680. Impure blood is received in the heart in the right auricle.

681. Plants take nitrogen in the form of Nitrate.

682. Washing soda in water behaves acidic.

683. The glad which maintains body temperature is the Pituitary gland.

684. Peeled banana under normal condition is brittle.

685. Phrenology deals with sensory perception of animals.

686. Vinegar is produced by two steps, first fermentation of sugar by yeast, second fermentation of

ethyl alcohol by bacteria.

687. The longest and the strongest bone in the human body is Femur.

688. Red color has the longest wavelength and violet has the shortest wavelength.

689. Chronometer is used to measure Time.

690. Carbon dioxide is used in fire extinguishers.

691. Hereditary disorders are the result of Defective DNA nucleus.

692. Pure gold is 24 carat.

693. One horse power is equal to 746 watts.

694. Dynamo is a device that converts Mechanical energy into electrical energy.

695. The minimum velocity required to escape from the gravitational pull is 11.2 km/s.

696. Heavy water consists of Oxygen and heavy hydrogen.

697. Polio is a viral disease.

698. Ag is the symbol for silver.

699. Babbage is called the father of computer.

700. Dead red blood cells are stored in liver.

Oxygen

46.1% , 461,000

Silicon

28.2% , 282,000

Aluminum

8.23% , 82,300

Iron

5.63% , 56,300

Calcium

4.15% , 41,500

Sodium

2.36% , 23,600

Magnesium

2.33% , 23,300

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.

.

Potassium

2.09% , 20,900

Titanium

0.565% , 5,650

Hydrogen

0.14% , 1,400

701. Spring tides occur on new moon and full moon days because on these days Sun, moon and earth

are in a straight line.

702. Clayey soil is best suited for cotton.

703. The time interval between two beats of a normal human heart is 1 second.

704. The material used for bleaching paper pulp is Sodium hypochlorite.

705. Mercury has the smallest diameter.

706. The instrument, used for recording tremors of earth, is known as Seismograph.

707. Ionosphere makes the radio transmission possible.

708. Colour of the skin is due to the presence of Melanin.

709. Natural rubber is a protein.

710. Concave mirror can be used to focus sunlight.

711. Liver secrets bile.

712. When an object is transferred from the earth to the moon its mass remains unchanged.

713. The unit of sound is Decibel.

714. It is economical to transmit electric power at high voltage.

715. Diamond does not have a tetrahedral structure.

716. The unit to measure the supersonic speed is Mach.

717. The application of the principles of genetics to the improvement of human race is known

as Eugenics.

718. The penetration of x-rays through an object depends upon the object‘s Density.

719. Using Ultrasound, we can determine the Structure of the body.

720. The find the hidden secrets under the water, the ships and submarines use the Sonar system.

721. The dirt in the dirty water can be separated by using the Ultrasound.

722. Recording of brain waves from outer surface of head is called E.E.G (Electroencephalograph).

723. The first rocket launched by Pakistan was Rahber.

724. The first Nuclear power plant in Pakistan was established at Karachi.

725. Sodium benzoate is used for preservation of food grains.

726. Steel is more elastic than rubber because ratio of stress to strain is more.

727. Haemoglobin makes the blood look red.

728. Mercury is extracted from Cinnabar.

729. Cattle-bone powder is used as fertilizer as it is rich in Phosphorous.

730. Heating element of an electric heater Nichrome.

731. Dry sand appears bright while wet sand appears dark because of Reflection.

732. Acid rain contains high levels of Sulphuric acid.

733. A woman‘s voice is shriller than a man‘s due to smaller vocal chords.

734. The blood glucose level is commonly expressed as Milligram per decilitre.

735. Soft drinks such as colas contain significant quantities of Caffeine.

736. A small pouch containing silica gel is often found in bottles of medicine in tablet or powder

form because silica gel absorbs moisture.

737. Fluorescent tubes are fitted with a choke. The choke coil reduces current in the circuit.

738. For reproduction of sound, a CD (Compact Device) audio player uses a Laser beam.

739. When a CD (Compact Disc used in audio and video systems) is seen in sunlight, rainbow like

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.

colours are seen. This can be explained on the basis of the phenomenon of Reflection and diffraction.

740. If a U-238 nucleus splits into two identical parts, the two nuclei so produced will

be Radioactive.

741. The total genetic material within an individual is known as the Genome.

742. The part of the body directly affected by Pneumonia is Respiratory system.

743. As the amount of clay in a soil increases, its water retaining capacity increases.

744. ―O‖ blood group of human beings is a universal donor.

745. Amino acids are a product of the digestion of Protein.

746. Ptyalin is a starch digeting enzyme.

747. Pepsin, a digestive enzyme, is produced in the Stomach.

748. Milk is nearly a complete food by itself.

749. The acids turn the blue litmus paper Red.

750. Permanent magnets can be made from Cobalt.

751. Nights are cooler in the deserts than in the plants because Sand absorbs heat more quickly than

the earth.

752. Atmospheric pressure exerted on the earth is due to the Gravitational pull.

753. Fertilizer having high nitrogen content is Urea.

754. Potassium Carbonate is used for removing air bubbles from the glass during its manufacture.

755. The chemical name for ―baking soda‖ is Sodium Bicarbonate.

756. The snow on the mountains does not melt all at once when it is heated by the sun because it

reflects most of the heat from the sun.

757. First time AIDS was identified in 1983.

758. Anthrax is a bacterial disease.

759. Blood is formed in bone marrow in human body.

760. Quark is the smallest part of the matter discovered by the scientists.

761. Trachoma is a disease of the eye.

762. The heart of a normal adult human being weighs about 300 grams and that of woman 200

grams.

763. Heart pumps 5 litre blood per minute in a normal human adult (at resting position).

764. The part of the body directly affected by Rikets is bone tissue.

765. Histology is the study of tissues.

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.

6. SCIENTIFIC REASONS FROM PAST PAPERS

(95 To 2011):

1) The Earth bulges out at equator. Why?

Ans: This is due to the shape of the earth. The earth is not a true sphere but it is an ellipsoid.

The equatorial diameter of the earth is 12756.27 kms. While its polar diameter is 12713.505

km. the difference between its equatorial and polar diameter is about 43 kilometres. The

rotation of the earth on its axis produces a centrifugal force which increases its equatorial

diameter. That is why earth bulges at the equator.

2) The Sun appears red at sunset and sunrise. Why?

Ans: The sun appears red at the time of sunset and sunrise due to the scattering of light by

small particles of dust or smoke near the surface of the earth. The light travels relatively

without hindrance that is why the sun appears red at the time of sunset and sunrise.

3) The ozone layer in the atmosphere is necessary for our survival. Why?

Ans: ozone layer in the atmosphere is very necessary for plant and animal survival because it

is the absorber of ultraviolet rays which are very dangerous for animal health. Ultraviolet rays

cause cancer of skin, spotting of plants etc. that is why the ozone layer is necessary and

essential for animal as well as plant survival.

4) The sky from moon appears black. Why?

Ans: as the moon has no atmosphere, so the sky looks completely black when viewed from

the moon.

5) Roads are bent inwards on curves. Why?

Ans: The roads are bent inwards on the curves and at the turns because the bents avoid falling

outside and prevent the accidents.

OR

When an object turns in a circle it is influenced by a centrifugal force which pushes it away

from the centre of the circle. When vehicles turn on a road they fall outside under the

influence of centrifugal force. In this way there is danger of falling or slipping out of road at a

turn. Roads are made in a way that these bent inward at the turns to avoid falling outside and

to prevent accidents.

6) Australian continent has winter season when we have summer season in Pakistan.

Ans: the earth on its axis is not at a vertical angle to its orbit. It is inclined at an angle of

about. In this way when the northern hemisphere of the earth is inclined to the sun and getting

direct sun rays, southern hemisphere is inclined away from the sun and getting less direct

rays. Thus the northern hemisphere has summer season and southern hemisphere has winter

season. Pakistan is in the northern hemisphere while Australia is in the southern hemisphere.

So when there is winter in Australia there is summer season in Pakistan.

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.

7) Meat takes longer to cook on mountains.

Ans: The meat takes longer time to cook on the mountains because the atmospheric pressure

decreases with attitude and the boiling point of a liquid is directly proportional to the

atmospheric pressure.

8) Water remains cool in earthen pitcher.

Ans: This occurs due to the process of evaporation. Water gets cooled on evaporation. As the

earthenware pitcher is concerned, they have small pores. Water tends to come out of pores

and evaporates which results in cooling effect on the earthenware and water.

While in the metal pots there are no pores and evaporation does not take place. Besides metal

has tendency to absorb heat that why water does not get cooled in a metal pot.

9) Ice and salt mixture is used as a freezing agent by manual ice-cream makers.

Ans: In manual ice-cream making a mixture of salt and ice is always used because salt has

capacity to reduce the temperature of ice by decreasing its freezing point. That‘s why ice and

salt mixture is used as freezing agent in manual ice cream making.

10) It is not advisable to sleep under trees during the night.

Ans: During night the plants release carbon dioxide (CO2) which is a poisonous gas and

injurious to health. That is why it is not advisable to sleep under trees during night.

11) Why the green house operators paint their glass roofs white in summer?

Ans: White colour is the reflector of light and it absorbs less heat as compared to other

colours. As in summer there is already very hot season and heat is not required to that level.

That is why the green-house operators paint glass roofs white in summer season.

12) Water boils quicker on mountains.

Ans: On Mountains the pressure of the air is low due to height, as the air pressure decreases

with altitude. In this way, water boils quicker on mountains at temperature less than 100

degree centigrade, which is the boiling point of water at ground level.

13) Rainbow is produced in the sky after rainfall and sunlight.

Ans: After rain, many droplet of water travel in the atmosphere. When sun rays fall on these

droplets, dispersion of water occurs and droplets act as prism and produce a spectrum of

seven colours. That‘s why a rainbow is seen in the sky after rain.

14) Milk is considered as an ideal food.

Ans: Milk is considered as an ideal food due to following reasons:

a) It contains all constitute of balanced diet.

b) Milk contains fat.

c) Milk has high nutritional value because it contains proteins as well as minerals.

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.

15) Lunar eclipse last much longer than solar eclipse.

Ans: Lunar eclipse last longer than the solar eclipse because the length of the earth‘s umbral

shadow cone is more than three times the average distance between the moon and the earth,

so the shadow is relatively wide at the point where the moon crosses it.

16) Goitre is common in hilly areas.

Ans: Goitre is common in hilly areas because there is deficiency of Iodine in the water.

17) Detergents are better cleaning agents.

Ans: A detergent consists of hydrophilic and hydrophobic ends. In case of dirt the detergent

pushes the dirt off the wet surface of the fabric. The washing machine provides the agitation.

18) Decomposers are important for life.

Ans: Decomposers break down animal waste and dead organisms in order to get energy and

release free nutrients back into the ecosystem.

OR

Decomposers break down organics into nutrients, which can be used by living organisms to create

new life.

19) Places near sea are cooler in summer.

Ans: Sea water keeps the temperature moderate. In the summer season the places located near sea are

cooler due to the lower temperature of water.

20) Colour blindness is more common in men than women.

Ans: Women have the sex chromosomes XX, while men have the chromosomes XY. The gene for

normal colour vision is found on the X-chromosome. If a woman has one X-chromosome with the

gene and one without it, she will not be colour blind. On the other hand, a man with an Xchromosome

that is missing the gene has no ‘backup’. He will definitely be colour blind. Colour blind

women have both X-chromosomes missing the colour vision gene. This is less probable

mathematically than having just one X-chromosome missing the gene.

21) Light colours absorb less heat therefore these are not heated as much as the black colour.

Ans: Dark colours do not exactly absorb more heat, but they do convert a higher percentage of light

into heat. In the sun with a dark coloured shirt it gets hot, where a lighter coloured shirt would not get

nearly as hot. This is due to the amount of light being absorbed by the colour. The lighter the colour

the smaller is the range of visible light being absorbed and converted into heat. White objects reflect

all visible light, where black objects absorb all visible light.

22) Rain water is more fertile than water from tube well.

Ans: Rain water is more fertile because it contains many salts and nitrogen dissolved from the

atmosphere.

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23) The manhole covers are generally round.

Ans: Manholes, which interconnect underground sewerage pipes, and serve as a point of entry for

cleaning the pipes, are located at every major sewer pipe junction, and are capped with round

manhole covers. The reason for the circular construction of these covers is, quite simply, that covers

of any other shape would fall through the manholes by virtue of their varying diameters. Circular

manhole covers do not vary in width, or in diameter, as is the case with these other shapes, thus

remaining in place despite the street traffic running roughshod over them.

24) Clothes of a moving dancer bulge.

Ans: The clothes of a moving dancer bulge outside due to the centrifugal force which tends to move

away from the centre.

25) People are advised not to stand near fast moving train.

Ans: One should not stand beside a fast moving train because of the strong pressure of air which

carries along. A man can fall in this pressure.

26) The image of a tree is inverted on the bank of a lake.

Ans: The water of lake acts as a mirror. According to the laws of light, mirror forms inverted images.

27) Polar star is always seen in the north.

Ans: It is because the Polar Star (North Star) is closest to the location of the celestial North Pole.

28) We never see birds urinating.

Ans: The birds do not have a urinary system like other living beings which possess urinary excretory

organs. In the birds the urine is excreted from body without special organs.

29) Pasteurized milk has more nourishment than the ordinary boiled milk.

Ans: Pasteurized milk is obtained by heating milk at a temperature of 60 degree Celsius for 30

minutes. In this way the TB bacteria are killed without damaging the milk protein. Thus pasteurized

milk has more nourishment than ordinary boiled milk.

30) Bees die when they sting human being.

Ans: Their stingers are actually ovipositors, tubular structures extending from the abdomen that

sometimes contain eggs. When the barbed stinger is left inside the victim, the honeybee mortally

tears her abdomen in the process. They leave their stingers in the wound with a tiny venom sac

attached. Fortunately, only about one out of a hundred people are allergic to bee sting, but allergic

reactions can be very serious.

31) Cloudy nights are usually warmer than the clear ones.

Ans: The clouds serve as a barrier and prevent the loss of heat. Thus the warm temperature is

maintained.

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.

32) Why do some people snore?

Ans: Some people snore during their sleep because the breathing action produces sound. This is so

because the pharynx or the windpipe offers resistance to the air taken in or expelled.

33) Why do we sometimes sleep walk?

Ans: Sleep walk is a sort of disorder of sleep in which a person starts walking during his sleep. The

sleeper walks and performs complex activities automatically without regaining consciousness.

34) Climbers bend forward while climbing mountain.

Ans: While climbing a mountain, a climber bends his body forward in order to keep the centre of

gravity of his body within two thirds portion. According to this principle the Pisa Tower is not

falling.

35) Why climbers get their food by climbing on other trees?

Ans: The climbers are mostly parasites and they cannot manufacture their food. Therefore, they

climb on other trees and get food from them.

36) Mars is called red planet.

Ans: Mars is called the red planet because its colour is red due to the desert like surface.

37) Vitamin D is the essential component of the body.

Ans: Vitamin D is necessary for body because it is essential for bone formation and retention of

calcium in the human body. Vitamin D also protects the teeth.

38) The weight of the object is less at the equator than at the poles.

Ans: The weight of an object is the product of mass and force of gravity. The equatorial diameter is

more than the polar diameter. Thus, the force of gravity is more at the poles and the weight is more

there.

39) The dogs pant, the birds open their mouth and the elephants move rapidly their ears.

Ans: All of them do not sweat; they use the above mentioned mechanisms to cool themselves.

40) A geostationary satellite appears standstill to a viewer on the equator of earth.

41) Why do the stars twinkle?

Ans: The light from the stars travels through different layers of space of varying densities. Therefore,

the light rays deviate from their original path. Further, these layers are not stationary but keep on

moving. This leads to the twinkling of stars.

42) On what days do we have equal days and nights all over the world? And why?

Ans: On 23 September and 21 March we have equal days and nights all over the world. This is so

because on these days, the rays of the sun fall vertically on the equator at noon. Both the poles

receive equal rays of the sun. As a result, exactly one-half of each hemisphere receives the sun‘s rays.

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.

This makes day and night equal.

43) Every fourth year has 366 days. Explain.

Ans: One revolution of the earth around the sun takes 356 days and 6 hours. But we consider a year

as consisting of only 365 days and ignore 6 hours. In four years the difference becomes as much as

24 hours or one day. Hence, to every fourth year we add one day. That year of 366 days is known as

leap year.

44) Why are igneous rocks called primary or parent rocks?

Ans: Igneous rocks are formed when the molten material from volcanoes gets solidified. This

material is liquid, hot and sticky which moves towards the surface through cracks and joints. All

other rocks derived from these rocks. Hence, they are called primary or parent rocks.

45) Why are the areas lying between the Arctic Circle and the North Pole in the Northern

Hemisphere and the Antarctic Circle and the South Pole in the Southern Hemisphere very cold?

Ans: These areas are very cold because the sun does not rise much above the horizon. Therefore, its

rays are always very slanting which emit minimum heat. These areas being very cold are called

Frigid Zones.

46) Why are the three hot regions of the world-equatorial forests, savannah lands and hot deserts-not

found in Europe?

Ans: The three hot regions of the world-equatorial forests, savannah lands and hot deserts-are not

found in Europe because Europe is the only inhabited continent situated entirely outside the tropics.

47) Why is the lowest layer of the atmosphere in contact with the earth‘s surface, the warmest?

Ans: The lowest layer of the atmosphere in contact with the earth‘s surface is the warmest because

the atmosphere is heated mainly from the below.

48) Why does the temperature above the ocean and land masses vary even on the same latitude?

Ans: Temperature above the oceans and land masses varies even on the same latitude because of the

differential heating of land and water, i.e., land mass is heated and cooled more rapidly and to a

greater degree than water.

49) Why are marine animals able to live at great depths than marine plants?

Ans: As marine animals do not depend upon sunlight for their survival, they are able to live at great

depths where there is permanent darkness.

50) Why do trees of coniferous forests possess needle-like leaves?

Ans: The needle-like leaves limit transpiration and thus enable conifers to grow in the drier areas.

51) Why do equatorial forests appear evergreen?

Ans: In equatorial forests trees often shed a few leaves or shed their leaves seasonally, but most of

the trees retain their leaves for most of the time so that the forests appear evergreen.

52) Why is petroleum often called black gold?

Ans: Petroleum is often called black gold because of its great demand in the modern industry and for

domestic use. It provides fuel for heat and lighting, lubricant for machinery and raw material for a

number of industries.

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53) Why are the kangaroos called marsupials?

Ans: Marsupial means broad-pouch. Since kangaroos have a pouch-like fold of skin near the stomach

in which they carry their young ones, they are called marsupials.

54) Why is platypus considered a strange animal?

Ans: Platypus is a strange animal because it is an animal-bird that survives under water, walks on the

ground and digs tunnel under the ground. It is a four-legged animal that lays eggs like a bird. It is

found in Australia.

55) Why is a person in moving vehicle thrown forward when the vehicle stops suddenly?

Ans: A person in a moving vehicle is in a state of motion. When the vehicle suddenly stops his body

tends to remain in a state of motion due to inertia and he is thrown forward.

56) Earth is continuously pulling moon towards its centre. Why does not the moon fall on to the

earth?

Ans: it is so because the gravitational attraction of the earth provides the necessary centripetal force

to the moon for its orbital motion around the earth due to which the moon is revolving around the

earth.

57) Which of the two-glass or rubber is more elastic and why?

Ans: Glass is more elastic than rubber because for a given applied force per unit area, the strain

produced in glass is much more than that produced in rubber.

58) Animal like camel can easily walk in the desert sand while other animals like donkeys, dogs and

horses cannot. Explain.

Ans: The camel has very broad and large feet. As a result of the large surface area in contact with the

ground, it exerts less pressure on the sand and sinks only slightly in it. Other animals have smaller

feet which exert more pressure on the sand. As a result, they sink more in the sand and cannot walk

easily in desert.

59) Why does a small quantity of liquid assume spherical form?

Ans: A small quantity of liquid assumes a spherical form due to surface tension which tends to

reduce the surface area. A given mass will acquire minimum surface area if it assumes a spherical

shape.

60) Why does an iron needle float on clean water but sink when some detergent is added to this

water?

Ans: Due to surface tension, the free surface of liquid at rest behaves like a stretched membrane.

When an iron needle floats on the surface of clean water, its weight is supported by the stretched

membrane. When some detergent is added to this water, its surface tension decreases. As a result of

it, the stretched membrane on the surface of water is weakened and is not able to support the weight

of needle. Hence the needle sinks in such water.

61) Why is cooking quicker in a pressure cooker?

Ans: The boiling point of water depends upon the pressure on its surface. Steam produced inside the

cooker builds up pressure thereby raising the boiling point of water, which results in quick cooking.

62) Why does steam cause more severe burns than boiling water?

Ans: The amount of heat (latent heat) possessed by steam is much greater than the amount of heat

possessed by water at the same temperature. Therefore, steam causes more severe burns than boiling

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water.

63) Why does ice not melt readily when salt is sprinkled over it?

Ans: When salt is sprinkled over ice, some of it dissolves. As dissolution of the salt is accompanied

by absorption oh heat. The temperature of the system falls below 0 degree Celsius. Hence, ice does

not melt readily.

64) It is difficult for firemen to hold a hose, which ejects large amount of water at a high velocity.

Why?

Ans: the water which comes out of the fireman‘s hose carries large momentum as its velocity is very

high. The equal and opposite reaction force pushes the fireman backwards with a great speed

satisfying the law of conservation of momentum. As a result, it is difficult for the fireman to hold the

hose.

65) In the outer space astronauts talk to each other through radios. Why?

Ans: sound waves need a material medium for its propagation. There is no air in space and hence,

sound waves cannot travel. However, radio waves can travel through space. The astronauts can see

each other because light, like radio waves, can travel through vacuum.

66) Sonar scanners are used by doctors. Explain.

Ans: sonar scanners send out ultrasonic waves, which are reflected by body tissue and organs. From

the pattern of reflections, a computer can build up an image of the internal structure which is vital for

diagnosis.

67) Why the flash of lightning is seen before the sound of thunder is heard?

Ans: the velocity of light is much greater than that of the sound. Therefore, flash of lightning is seen

before the sound of thunder is heard.

68) Bats have poor eyesight but are able to home their prey with great accuracy. Also, dolphins can

avoid fishing nets and can detect fish at night. Explain

Ans: Bats emit high frequency (1, 20,000 Hz) sound waves and listen with their sensitive ears for any

echoes. From the time taken to hear the echo and from the nature of sound received. Bats are able to

estimate the distance and the type of surroundings. This process is known as echolocation. Same

process is used by the dolphins.

69) When low flying aircraft passes overhead, we sometimes notice a slight disturbance on our TV

screen. Why is it so?

Ans: a low flying aircraft reflects TV signal. Due to the interference between the direct signal and the

reflected signal, there is disturbance on the TV screen.

70) In automobiles, why are convex mirrors used to see the traffic from behind?

Ans: Convex mirrors are used in automobiles because they form erect and diminished images of the

object. Thus, it helps the drivers to get a wider field of view of the traffic coming from behind.

71) Why is mirage formes in the deserts?

Ans: A mirage is formed owing to total internal reflection. To the observer at a distance, the reflected

image of the object appears behind the reflecting surface, as if the object were in front of it, but

actually it is just an illusion.

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72) What will be the colour of grass in blue light?

Ans: Grass will appear blackish in colour in blue light because it has the property of absorbing all

other colours except its own colour. The blue rays falling on grass will be absorbed by it, and it will

appear dark coloured.

73) A bird perches on a bare high power line and nothing happens to it. A man standing on the

ground touches the same line and gets a fatal shock. Why?

Ans: When bird perches on a live high power line, no current passes through the body of bird because

there is no potential difference between live wire and the body of bird as the potential of bird‘s body

is the same as that of wire.

When a man standing on the ground touches the same wire then due to a large potential difference

between his hands and feet, a large current flows through his body to the earth.

74) During lightning it is safest to be inside a car rather than under a tree or in the open. Give reason.

Ans: When a person is in the open or under the tree, the lightning passes through his body to the

earth. On the other hand, for a person inside a car, the car provider shielding and the electric field

inside the car is zero, thus lightning does not affect the person inside it. The lightning actually passes

through the metallic body of the car to the earth without affecting the person sitting inside it.

75) Why is earthing desirable for electric appliances?

Ans: Earthing helps the current move into the earth in the event of short-circuit, without giving a

shock to the user.

76) Why does a perspiring man feel relief when air flows by his side?

Ans: The air flowing by the side of a perspiring man quickens the pace of evaporation of perspiration

from the body of that person, and the resultant loss of heat from his body causes the cooling sensation

which provides relief to him.

77) Why is magnet always made of soft iron?

Ans: Magnet is always made of soft iron because ‗magnetisation‘ and ‗demagnetisation‘ both are

possible in soft iron.

78) Why are telephone wires between two poles kept loose?

Ans: Telephone wires are kept loose between two poles so that they are protected from being broken

due to expansion and contraction caused by the change of temperature in summers and winters.

79) X-rays penetrate through the flesh but not through bones. Why?

Ans: The penetrating power of X-rays depends upon the potential difference between the cathode and

the anode of X-ray tube. The X-rays produced can penetrate through light element like flesh of

human body but they are unable to penetrate through heavier elements like bones.

80) What is a black hole? Why is it called so?

Ans: A black hole is a super dense planetary material formed due to the death of a star of mass more

than five solar masses.

It is called black hole because any particle or photon approaching its surface is just swallowed by it.

It appears black, as radiation is neither emitted nor reflected by it.

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81) Why do water pipes burst in severe cold winters?

Ans: Water freezes in pipes during winters, when the temperature goes below 0 degree Celsius (i.e.,

freezing point of water). It expands and in the process exerts pressure on the water pipes, thereby

sometimes bursting them.

82) Most aircrafts and ships have their front shape pointed. Why?

Ans: The shape of many objects, viz. aeroplanes, rockets, ships, etc. moving through air or water, are

designed in such a way that friction can be reduced between the objects and air/water. Such type of

body is known as streamlined and the process is known as streamlining.

83) An athlete runs some distance before taking jump, why?

Ans: An athlete runs a certain distance before actually jumping in order to increase his speed, and

thereby, his inertia of motion. This increased inertia of motion enables him to jump a longer distance.

84) It is difficult to drown in the Dead Sea. Why?

Ans: The water of Dead Sea has a salt content of 27%. Therefore, its density is much greater than that

of ordinary sea water and it also offers a greater upthrust. Hence, the body weighs less than an equal

volume of Dead Sea water and is thus, able to float.

85) Why aquatic animals have soft skeleton unlike those of the terrestrial animals?

Ans: The density of animals and fish living in water is almost the same as the density of water.

Therefore, their weight is almost completely balanced by buoyancy. That is why they do not need

massive skeleton like those of terrestrial animals.

86) Why does a swimming pool appear less deep than it really is?

Ans: When rays of light start from the bottom of a pool and travel from water to air, they are

refracted away from the normal because they travel from a denser medium to a rarer medium. As a

result, a virtual image of bottom is formed above the bottom. Hence, a swimming pool appears less

deep than it really is.

87) Why is electrical wiring in parallel better?

Ans: electrical wiring in parallel is better because all the lines will have the same potential difference

and if one line gets fused the other lines remain unaffected.

88) It is easier to swim in sea water than in river water. Explain.

Ans: The density of sea water is more than that of the river water. Therefore, the weight of sea water

displaced by the swimmer is more. Thus, buoyant force of upthrust on the swimmer increases,

making it easier to swim in sea water.

89) A cold compress is applied on the forehead of a person suffering from high fever. Why?

Ans: Evaporation causes cooling. As the water evaporates, it absorbs heat from the forehead and

helps in reducing the temperature.

90) A man with a load his head jumps from a high building. What will be the load experienced by

him.

Ans: Zero, because the acceleration of his fall is equal to the acceleration due to gravity of the earth.

91) Why is spring made of steel and not copper?

Ans: The elasticity of steel is greater than that of copper.

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92) Why is it easier to spray water to which soap is added?

Ans: Addition of soap decreases the surface tension of water. The energy for spray is directly

proportional to surface tension.

93) A piece of chalk when immersed in water, emits bubbles. Why?

Ans: Chalk consists of pores forming capillaries. When it is immersed in water, the water begins to

rise in the capillaries and air present there is expelled in the form of bubbles.

94) Why does a liquid remain hot or cold for a long time inside a thermo flask?

Ans: Because of the presence of air, which is poor conductor of heat, in between the double glass

walls of a thermos flask.

95) Why is the boiling point of sea water more than that of pure water?

Ans: Sea water contains salts and other impurities with different points which jointly rise its boiling

point.

96) Why is it recommended to add salt in water while boiling grams?

Ans: By addition of salt the boiling point of water gets which helps in cooking.

97) Why is soft iron used as an electromagnet?

Ans: Because it remains magnetic only till the current passes through the coil and loses its magnetism

when the current is switched off (principle of electric bells)

98) Why does ink leak out of a partially filled pen when taken to a high altitude?

Ans: As we go up the pressure and the density of air go on decreasing. Partially filled pen leaks when

taken to a higher altitude because the pressure of air acting on the ink inside the tube of the pen is

greater than the pressure of air outside.

99) Why does some liquids burn while others do not?

Ans: A liquid burns if its molecules can combine with oxygen of the air with the production of heat.

Hence, oil burns but water does not.

100) Oil and water do not mix. Why?

Ans: i) Molecules of oil are not bigger than that of water and therefore do not mix easily.

ii) Molecules of water are polar, i.e. they have opposite charges at two ends whereas oil molecules do

not; as a consequence they tend to stay away from water molecule.

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7. Differences

1. Artery & Vein

Artery

i) Arteries are blood vessels which transport blood away from the heart.

ii) Arteries have thick vascular walls.

iii) The inside bore or lumen of arteries is narrow.

iv) Arteries carry oxygenated blood with the exception of pulmonary artery.

v) The walls of arteries are more elastic.

vi) The blood is under great pressure in the arteries.

vii) Arteries are generally deeply placed.

viii) Arteries end in the capillaries.

Vein:

i) Veins are the blood vessels which always carry blood towards heart.

ii) Veins have thin muscular walls.

iii) The inside bore or lumen of veins is wide.

iv) Veins carry deoxygenated blood with the exception of pulmonary veins.

v) The walls of veins are less elastic.

vi) The blood is under less pressure in the veins.

vii) Veins are generally superficially placed.

viii) Veins start from the capillaries.

2. PNP and NPN Transistor

1. NPN has higher electron mobility than PNP. Therefore, NPN bipolar transistors are often more

favoured than PNP transistors.

2. NPN is easier to create from silicon than PNP.

3. The main difference of NPN and PNP is the base. One is just the opposite of the other.

4. With the NPN, a P-dope semiconductor is the base, while with the PNP, the ‗base‘ is a N-dope

semiconductor.

3. Electronic & Static Electricity

Electronic Electricity

i) This is electricity in motion.

ii) It involves flow of electrons.

iii) It has high voltage.

Static Electricity:

i) This is electricity at rest.

ii) It does not involve flow of electrons.

iii) It has low voltage.

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4. Concave & Convex Lens

Concave Lens

i) It is the lens which is narrower in the centre and broader towards the corners.

ii) When a beam of light strikes a concave lens all the rays after passing through it diverge.

iii) It gives mostly virtual image.

iv) They are also called diverging lenses.

Convex Lens:

i) It is the lens which is narrower towards the corners and broader towards the centre.

ii) When a beam of light strikes a convex lens all the rays after passing through it converge at a single

point.

iii) Mostly real images are formed except when the ray of light passes through it when object is

palced between optical centre and focus.

iv) They are also called converging lenses.

5. Absorption & Adsorption

Absorption

i) Absorption is a process in which a substance takes up another substance, such as blotting paper

(solid) absorbing water (a liquid). OR Adsorption and absorption are two different things. Absorption

is the chemical integration of one chemical into another. When you drink a glass of water, you are

absorbing it, as the water becomes part of you.

Adsorption:

i) Adsorption is a process in which a substance adheres to the surface of another substance.

Adsorption is important in some types of catalysis, notably where gases adsorb on metal surfaces.

The reaction is then made easier by a consequent lowering of activation energy. OR Adsorption

occurs when one substance holds another via physical bonds. If you spill a glass of water on your

shirt, it is adsorbed as the fibres will hold the water until heat dries out the shirt.

6. Fats & Oils

Fats

i) are solid at room temperature

ii) made by animals, mostly

iii) are more saturated

Oils:

i) are liquid at room temperature

ii) are made by plants, mostly

iii) are less saturated

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Hypoglycaemia:

i) The fall in sugar level in the blood below the normal physiologic level known as Hypoglycaemia.

Normal physiologic range of sugar in blood is 60-90mg% at fasting and 120-140 mg% at random.

ii) It is treated by giving intravenous glucose.

iii) It causes mental confusion, visual problem and often coma etc.

iv) It causes weakness and increases in food desire.

Hyperglycaemia:

i) Hyperglycaemia is a condition in which blood sugar level rise above its normal range.

ii) It is treated by exercise, medicine or by intravenous insulin therapy.

iii) It causes weakness, calf pain, unhealed wounds and kidney problem.

iv) It causes excessive urination, dryness of lips and increased thirst etc.

2. Epidemic & Endemic

Epidemic:

i) If at one place and times a great number of people suffer from a disease is known as epidemic.

ii) It can travel from one place to another.

iii) Examples: Influenza, Smallpox, Cholera etc.

Endemic:

i) If a disease persists in a particular locality, certain area or one region, it is known as endemic

disease.

ii) It cannot travel from one place to another place.

iii) Example: Goitre in iodine deficient areas.

3. Herbivores & Carnivores

Herbivores

i) The animals eating green plants, grass and fodder are known as Herbivores.

ii) Animals have specific digestive system to digest leaves, plants and fodder.

iii) The teeth are specifically designed to cut and chew leaves, plants and fodder.

iv) Jaw movement is specific for side motion.

v) Examples: goats, cattle, sheep, buffalo, cow etc.

Carnivores:

i) The animals eating flesh and meat are known as carnivores.

ii) Digestive enzymes are specific.

iii) Their teeth are short and to cut and chew leaves, plants pointed especially for flesh eating.

iv) Jaw movement is specific for up and down movement.

v) Examples: Tiger, dog, cat, lion etc.

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4. Respiration & Photosynthesis

Respiration

i) Respiration is a catabolic process in which compounds are broken down.

ii) In this process carbohydrates are broken down into simpler compounds.

iii) The end-products for this process are CO2 and H2O.

iv) In respiration Oxygen enters the plant body and CO2 is released.

v) It occurs during both day and night. Light is not necessary for this process.

vi) In respiration energy is released from food material.

Photosynthesis

i) It is an anabolic process in which compounds are formed.

ii) In this process carbohydrates are manufactured.

iii) The end-product of this process is simple carbohydrates.

iv) In photosynthesis CO2 enters the plant and O2 is released.

v) It occurs during day time only. Light is essential for this process.

vi) It is energy consuming process.

5. Pollination & Fertilization

Pollination

i) It is a process involving transfer of pollens form male reproductive organ to female reproductive

organ of plants.

ii) It occurs in flowering plants.

iii) The products of pollination are seed.

iv) It takes place through animals, birds, insects, wind and water.

Fertilization:

i) In fertilization fusion of egg and sperm occurs.

ii) It occurs markedly in animals.

iii) The product of fertilization is zygote.

iv) It takes place by physical contact and mating of male and female.

Thermoplastics

i) Plastics that can be melted again and again are known as thermoplastics.

ii) They behave just like wax.

iii) These plastics can be shaped again and again.

iv) Examples: Nylon, PVC, Teflon etc.

Thermosetting Plastics:

i) Plastics that can be melted only once are known as thermosetting plastics.

ii) They become hard after melting.

iii) These plastics cannot be shaped again and again.

iv) Examples: Polyesters and Bakelite.

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Lunar & Solar Eclipse

Lunar Eclipse

i) It occurs when the earth comes between moon and sun.

ii) Moon goes through series of partial eclipses when moon comes out of umbral region of earth‘s

shadow.

iii) Earth lies in umbral region at total eclipse when earth lies exactly between moon and sun and its

shadow covers the whole moon.

Solar Eclipse

i) It occurs when moon comes between earth and sun.

ii) Partial eclipse of sun occurs as in Penumbra can see a part of the sun.

iii) At the total eclipse of the sun, the shadow of moon which it throws on earth consists of an umbra

and penumbra people on earth who are in umbral region cannot see the sun.

Asteroid & Meteorite

Asteroid:

i) The small rocky objects which are orbiting the sun between orbits of Mars and Jupiter are known

as asteroids.

ii) Its origin is concentrated to the remains of planets that fell apart.

iii) Asteroid means star like but these are known as minor planets.

Meteorite:

i) Tiny chunk of material floating in space, which can also enter the earth‘s atmosphere and become

meteor are known as meteorites.

ii) It may originate by the disintegration of comet.

iii) A falling star (Meteor) is seen as a streak of light in sky.

Renewable & Non-renewable resources

Renewable Resources

i) Renewable resources are used continuously and can be used again and again.

ii) Major examples are: air, water, soil, wildlife, forests, fish etc.

iii) These resources support millions of people all over the world.

iv) Renewable resources are constantly renewed by bio-geochemical cycles of nature.

Non-renewable Resources

i) Non-renewable resources cannot be used again and again after their consumption.

ii) Major examples include: Coal, oil, natural gas etc.

iii) These resources cannot support millions of people all over the world.

iv) Non-renewable resources are being exhausted day by day because their demand rises. Due to

worldwide demand of fossil fuels, its supplies are declining.

OR

Renewable resources-

1) the resources that can be renewed by reproduction are called renewable resources.

2) Renewable resources are inexhaustible.

3) Renewable resources are not affected by the human activities.

4) All biotic resources are renewable.

5) For example: air and water.

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Non-renewable resources-

1) the resources that are present in fixed quantities are called non-renewable resources.

2) Non-renewable resources are inexhaustible.

3) Non-renewable resources are affected by human activities.

4) Some abiotic resources are non-renewable.

5) For example- fossil fuels and minerals.

Endothermic & Exothermic Reaction

Exothermic Reaction

i) Energy is drawn in from the external environment, causing its surroundings to loose heat, or “cool

down.”

ii) The endothermic chemical reaction creates a product that has a higher energy level than the

original materials, causing the reactant’s stored energy to decrease. (In scientific terms, the reactants

have “less total enthalpy” than the product.)

iii) The resulting product of the reaction is less stable because, the higher the energy bond, the less

strength its molecules possess.

iv) Most endothermic reactions are not spontaneous.

v) Example: Melting ice. In order for ice to melt, it needs to draw in the heat (energy) from its

surroundings. The ice becomes less stable as it responds to the increased heat. The ice stored energy

decreases. The end product is water, which has a higher energy level than the ice.

Exothermic Reactions

i) Exothermic chemical reactions cause their surroundings to warm up by giving off heat.

ii) The reactants contain more stored energy than the product because energy from external sources is

not required, but given off. This gives the product more stability due to the lower amount of energy

needed. (In this case, the reactants have a “greater total enthalpy” than the product.)

iii) Exothermic reactions are usually spontaneous.

iv) Example lighting a match. When the head of the match is struck, it results in the spontaneous

release of stored energy (heat) from the reactants into the surroundings. The flame that is produced

has a lower level of energy than the match and the striking surface because the reaction is giving off

stored energy and not required to draw energy in from its surroundings

Star & Planet

Star

i) Stars are self-luminous heavenly bodies.

ii) They do not revolve around the sun.

iii) They are usually stationary.

iv) Examples: fixed stars, binary stars.

Planet:

i) Planets are rocky non-luminous bodies.

ii) They revolve round the sun.

iii) They usually move.

iv) Examples: Mercury, Venus, Jupiter etc.

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Nuclear Fission & Fusion

Fission:

i) Lighter atoms are fused together at a very high temperature to form heavier elements.

ii) It is difficult to carry out on the earth.

iii) It has no nuclear waste problem.

iv) It requires cheaper and abundant elements.

v) Not possible at concerning scale as high temperature is needed to start it.

Fusion:

i) Heavier unstable atoms are broken down to produce energy.

ii) It is easy to carry out on the earth.

iii) It has nuclear waste radioactivity disposal problem.

iv) It requires expensive and rare elements.

v) Possible to commercialize under controlled measure.

RAM

i) It stands for random access memory.

ii) It is an optical disc, where data and information is stored permanently.

iii) RAM is the primary storage media.

iv) RAM is the primary storage device from which the system boots.

v) RAM is stored on RAM chip.

vi) The data or information stored on it can be written on or it can be erased.

ROM

i) It stands for read only memory.

ii) It is that part of CPU, where temporary information is stored.

iii) RIOM is the secondary storage media.

iv) System does not boot from ROM.

v) ROM is stored on a compact disc.

vi) The data or information stored on it neither be written on, nor it can be erased.

BIT & BYTE

A bit is defined as: a single basic unit of information, used in connection with computers and

electronic communication. All modern computers store and use data in digital form. The smallest unit

of storage and measurement is one binary digit, therefore its name.

A byte, pronounced ‗bite‘, is the next size up basic unit of measurement for information storage,

usually consisting of eight bits. These 8 bits are grouped together to form a byte that is, a total or 8

grouped bits representing one character of data.

Therefore, so far we have two basic units of measuring digital information storage that have different

capacities, they are:

• 1 Bit

• 8 Bits equal 1 Byte

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CU & ALU

CU

i) It stands for Control Unit.

ii) Control unit controls overall activates of computer.

iii) CU does not perform the functions of calculations.

ALU

i) It stands for arithmetic logic unit.

ii) It performs arithmetic and logical operations.

iii) ALU performs functions of addition, subtraction, multiplication and division.

Hardware & Software

Hardware:

i) All the physical components of computer which can be touched, measured have weight and occupy

space are collectively called computer hardware etc.

ii) Examples of hardware are: keyboard, mouse, joy stick, scanner, printer, CPU etc.

Software:

i) Software can be defined as a set of instructions and codes written in a defined manner. In other

words software are pre-written programs, which control the operation of computer.

ii) Examples of software are; DOS, windows, UNIX, XENIX, Linus, JAVA, Oracle, Antivirus etc.

PC/Minicomputers & Mainframe computers

PC:

i) It is a small computer based on microprocessor.

ii) One user can use it at a time.

iii) These are very low priced computers. An individual can afford it.

iv) User friendly software are used to operate this computer.

v) Minicomputers were launched in 1959 by Digital Equipment Corporation (DEC)

vi) Minicomputers are also made by Data General, Hewlett-Packard & IBM

Mainframe Computers:

i) The largest computers called mainframe computers are the oldest category of computer system.

ii) They are capable of great processing speed and data storage.

iii) These are always kept in air-cooled rooms.

iv) They are mainly used in banks, airlines and industrial companies.

Email & Snail Mail

Snail mail:

i) “Snail mail” is a term used to refer to mail that is sent in the traditional way — through the postal

service — rather than by email, fax, or other electronic means of communication.

ii) It is called “snail mail” because it can be very slow, as is a snail. Snail mail generally takes 2 or 3

days to go from origin to destination, if not many more,

iii) Snail mail has gone out of fashion for simple letters, though it is still necessary for sending

packages, or legal documents that require signatures.

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Email:

i) Email is electronic mail which is very quick means of communication through computers and

telephone line.

ii) Email can be sent instantly.

iii) With email, a message is sent directly from a user’s mail program to another person’s email

address. Though many email messages simply contain words, they may also include photos or other

digital files, such as songs, or links to websites.

Apes & Monkeys

Apes:

i) Apes do not have tail.

ii) Apes have rounded nasal openings.

iii) Apes generally have bigger brains and larger bodies than monkeys.

iv) Apes do not have web foot.

v) Apes are bigger in size.

vi) Apes are: Humans, Chimps, Gorillas, Orangutans and Gibbons.

Monkeys

i) Monkeys have tails.

ii) Monkeys have slanted nasal openings.

iii) Monkeys have web foot.

iv) Monkeys are smaller in terms of size

v) Monkeys are all primates non-apes and non-prosimians (lemurs)

Hydrostatics & Hydrodynamics

Hydrostatics:

i) Hydrostatics is a branch of science which deals with physical behaviour of liquids at rest.

ii) The consideration of liquids at rest, involves problems of buoyancy and flotation, pressure on

dams and submerged devices, and hydraulic presses.

Hydrodynamics:

i) Hydrodynamics is the branch of science which deals with behaviour of liquids in motion.

ii) The study of liquids in motion is concerned with such matters as friction and turbulence generated

in pipes by flowing liquids, the flow of water over weirs and through nozzles, and the use of

hydraulic pressure in machinery.

Comet & Meteor

Comet:

i) Comet is a collection of gas, dust, and volatile ice that travel around the sun, generally in very

eccentric orbit.

Meteor:

i) Meteor is a streak of light seen in the night sky signify the burning up in earth‘s atmosphere of

inter-planetary material.

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Barrage & Dam

Barrage:

i) Barrages are constructed not at a much height but at a low height.

ii) Barrages are single purpose constructions i.e. for irrigation.

iii) Electricity cannot be produced in barrages.

iv) It is constructed on plains.

v) Sukkur barrage is an example.

Dam:

i) Dams are constructed at higher elevation or at a height.

ii) Dam is multipurpose. It acts as reservoir, control flood, and for irrigation.

iii) Dam is constructed to generate electricity.

iv) It is impossible at ground level.

v) Tarbella dam is an example.

Isotopes:

These are the elements having same atomic number but different mass number. They have

the same atomic number because the number of protons inside their nuclei remains the same.

The difference in their mass number is due to the difference in their number of neutrons.

Isobars

Where Isotopes are chemically the same and physically different, the converse is true in

Isobars. That is isobars are elements, which are chemically different but physically the same.

So, isobars are atoms of different elements having the same atomic mass but different atomic

number. Since their number of electrons is different, their chemical properties are different.

The light nuclei have unstable isobars. Heavy nuclei have stable isobars and these occur in

pairs. Suppose the number of protons of one isobar matches with that of another they are

called as mirror-nuclides of each other.

Autopsy & Biopsy

Autopsy:

i) An autopsy is the dissection and analysis of a dead subject.

ii) , autopsies are limited to the deceased and there are two kinds of autopsy; External

examination and internal examination.

iii) Autopsy is performed for medico-legal purpose.

Biopsy:

i) A biopsy is a medical test in which cells, tissue, or fluid is removed for examination.

ii) Biopsy is not limited to only living people because they are routinely taken from organs

that are going to be used for transplantation.

iii) Autopsy is performed for diagnosis purpose.

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Mitosis & Meiosis

Mitosis:

i) Mitosis takes place within somatic cells (cells that make up the body).

ii) One single division of the mother cell results in two daughter cells.

iii) A mitotic mother cell can either be haploid or diploid.

iv) The number of chromosomes per nucleus remains the same after division.

v) It is preceded by a S-phase in which the amount of DNA is duplicated.

vi) In mitosis, there is no pairing of homologous chromosomes.

vii) There is no exchange of DNA (crossing-over) between chromosomes.

viii) The centromeres split during anaphase.

ix) The genotype of the daughter cells is identical to that of the mother cells.

x) After mitosis, each daughter cell has exactly same DNA strands.

Meiosis:

i) Meiosis takes place within gamete cells (sex cells).

ii) Two divisions of the mother cell result in four meiotic products or haploid gametes.

iii) A meiotic mother cell is always diploid.

iv) The meiotic products contain a haploid (n) number of chromosomes in contrast to the (2n)

number of chromosomes in mother cell.

v) In meiosis, only meiosis I is preceded by a S-phase.

vi) During prophase I, complete pairing of all homologous chromosomes takes place.

vii) There is at least one crossing-over or DNA exchange per homologous pair of

chromosomes.

viii) The centromeres do separate during anaphase II, but not during anaphase I.

ix) Meiotic products differ in their genotype from the mother cell.

x) After meiosis, each daughter cell has only half of the DNA strands.

Hard water & Heavy Water

Hard Water:

i) Hard water is that type of water which does not form lather easily.

ii) Its formula is H2O.

iii) Hard water is not used in nuclear power plants.

Heavy Water:

i) Heavy water is deuterium oxide in which hydrogen of water is replaced by its heavier

isotope, Deuterium.

ii) The formula of heavy water is D2O.

iii) Heavy water is used in nuclear power plants.

Climate & Weather

Climate:

i) Climate is the normal weather conditions for an area during a season or a year.

ii) Climate of an area is described by means of an average means of an average of the

statistics of the various weather factors over a period of time, normally 30-years.

Weather:

i) Weather is the condition of the atmosphere at any one place and time.

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ii) Weather is described by air, temperature and humidity, wind speed and direction, cloud

amount and precipitation, sunshine and visibility.

Cardiac & Skeletal Muscles:

Cardiac Muscles:

i) Cardiac muscles are present in the heart only.

ii) They have centrally placed nuclei.

iii) They never fatigue.

iv) They are composed of long fibres.

v) They are under involuntary control.

Skeletal Muscles:

i) Skeletal muscles are present in the skeleton of the body.

ii) Nuclei are not centrally placed in skeletal muscle.

iii) They can fatigue.

iv) They are not composed of long fibres.

v) They are under voluntary control.

Haze & Smog

Haze:

i) The dust particle smoke etc. that may be visible in atmosphere close to the earth‘s surface

is known as Haze.

ii) It does not affect natural visibility.

iii) It does not occur particularly near coastal areas.

Smog:

i) It is a mixture of solid and liquid fog as well as particles of smoke. It is formed when

humidity is high.

ii) Smog reduces visibility.

iii) It occurs near coastal areas.

Enzyme & Hormone

Enzyme:

i) These are organic catalysts produced in the protoplasm of all living cells.

ii) These are mostly protein in nature.

iii) They control all biochemical reactions of the cell.

iv) These are present in all cells and show their activity there.

Hormone:

i) These are organic substances produced in places away from their functional sites.

ii) These are mostly acids.

iii) They promote and inhibit growth, flowering, sex expression, etc.

v) These are mobile. They are produced at one site and show their activities at other sites.

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Igneous & Sedimentary Rocks

Igneous Rocks:

i) Igneous rocks are formed when magma (or molten rocks) has cooled down and solidified.

ii) Igneous rocks are commonly found inside the Earth‘s crust or mantle,

iii) Igneous rocks can be an important source of minerals,

iv) Examples of Igneous rocks include granite and basalt.

Sedimentary Rocks:

i) Sedimentary rocks are formed by the accumulation of other eroded substances,

ii) Sedimentary rocks are usually found in water bodies (sea, oceans etc.).

iii) Sedimentary rocks, or their bedding structure, are mostly used in civil engineering; for the

construction of housing, roads, tunnels, canals etc.

iv) Examples of Sedimentary rocks include shale, limestone and sandstone.

OR

What is the difference between Igneous Rocks and Sedimentary Rocks?

– Igneous rocks are formed from molten liquid minerals called magma, while sedimentary

rocks are formed from lithification (cementing, compacting and hardening) of existing rocks.

– Igneous rocks are non-porous for water, while sedimentary rocks are porous to the water.

That is water cannot penetrate through igneous rocks but can through sedimentary rocks.

– Igneous rocks are having fossils very rarely, while sedimentary rocks are rich in fossils.

– Igneous rocks are harder than sedimentary rocks.

– Tendency to react with acids is higher to sedimentary rocks when compared to igneous

rocks.

– Igneous rocks may be light or dark coloured, while sedimentary rocks have great colour

variety.

Producers & Consumers

Producers:

Producers are organisms that make their own food through photosynthesis or other reactions

and are a food source for other organisms (ex. plants, extremophile benthos communities).

Consumers:

Consumers are organisms that ingest other organisms, like plants, in order to gain energy (ex.

herbivores, carnivores, omnivores, and detrivores).

Microcomputer & Minicomputer

Microcomputer:

i) A microcomputer is a standard desktop computer used at a home and in business.

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ii) A microcomputer is a computer with a microprocessor as its CPU.

iii) They are cheap, compact and can be easily accommodated on a study table.

iv) Microcomputer is a single-user computer.

v) The two most common types of storage devices used with microcomputers are tapes and

disks.

vi) Microcomputer is not powerful or as fast as minicomputer.

-vii) Examples are- Modern computers like desktop, laptop etc.

Minicomputer:

i) Minicomputers are mid-sized computer used in universities, research labs and small

corporations.

ii) Minicomputers are faster than microcomputers.

iii) They are expensive and larger than microcomputer.

iv) Minicomputer is a multi-user computer.

v) For secondary storage, most minicomputers use magnetic disks or tapes.

vi) Minicomputer is powerful than microcomputer but not as super computer and mainframe

computer.

vii) Examples are- IBM 9375, Motorola 68040 etc.

Mainframe & Super Computers

Mainframe Computers:

i) The largest computers called mainframe computers are the oldest category of computer

system.

ii) They are capable of great processing speed and data storage.

iii) These are always kept in air-cooled rooms.

iv) They are mainly used in banks, airlines and industrial companies.

Super Computers:

i) The super computers are fastest of all computers.

ii) It was invented by two brothers Gregory and David in New York.

iii) These computers have high capacity to work.

iv) These also require air-conditioned rooms.

v) The super computers are mainly used in a) Automotive engineering b) Modelling nuclear

explosion c) Aeroplane designing d) Oil exploration e) Weather forecasting etc.

RAM & Cache Memory

RAM

i) It stands for random access memory.

ii) It is an optical disc, where data and information is stored permanently.

iii) RAM is the primary storage media.

iv) RAM is the primary storage device from which the system boots.

v) RAM is stored on RAM chip.

vi) The data or information stored on it can be written on or it can be erased.

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Cache Memory:

i) Cache memory is a special high speed memory that the CPU can access quickly.

ii) It is used in computers with very fast CPUs, so that these CPUs don‘t have to wait for Data

to be delivered from RAM.

iii) The most frequently used instructions are kept in the cache memory.

iv) This allows the CPU to run faster because it does not have to take time to swap

instructions in and out of RAM.

Rotation & Revolution Of Earth:

Rotation Of Earth:

i) it is the movement of the earth in which the earth makes rotation around its axis.

ii) Rotation of the earth occurs from West to East.

iii) The main effect of the rotation of the earth is the formation of days and nights.

Revolution Of Earth

i) it is the movement of the earth, in which the earth makes revolution around the sun.

ii) Revolution of the earth occurs in counter clockwise direction or from right to left.

iii) The main effect of the revolution of the earth is the change of seasons.

Dicot & Monocot Stem

Dicot Stem:

i) In dicot stem pericycle is broken.

ii) There are few vascular bundles.

iii) The vascular bundles are open.

Monocot Stem:

i) In monocot stem pericycle is not broken.

ii) there are many vascular bundles.

iii) The vascular bundles are closed.

Penumbra & Umbra

Penumbra:

The term relates to the solar and lunar eclipse. When during its revolution, the moon comes

between the sun and the earth then solar eclipse takes place. A shadow is created. The outer

shadow region in the eclipse is called penumbra.

Umbra:

Similarly, when the solar eclipse takes place, two regions of shadow are created. Out of these

the dark inner shadow region is called Umbra.

Nucleus & Nucleolus

Nucleus:

i) The nucleus is the main organelle.

ii) It is mostly present in the centre of the cell.

iii) It is membrane bound.

iv) The nucleus contains DNA.

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v) It contains hereditary material in the form of chromosome and genes and controls all the

activities of the cell.

Nucleolus:

i) The nucleolus is a sub-organelle.

ii) It is present in nucleus.

iii) It is non-membrane bound.

iv) It contains RNA.

v) It takes part in protein formation.

Lava & Magma

• Magma is the molten rock material deep inside earth‘s crust, while the same magma, when

it finds its way to a volcano through fissures and cracks, and comes out of the mouth of the

volcano, is referred to as lava.

• So magma is deep underground, while lava is the hot mixture of gases and molten rocks that

comes out of the volcano.

• The most notable difference between magma and lava pertains to their location.

Fold & Fault

Fold:

A fold is a bend in a rock layer caused by forces within the crust of the earth. Folds usually

occur in a series and look like waves in the rock.

Fault:

Rock layers can also break, in which case a fault occurs. A fault zone is where the sides of

broken rock have moved relative to each other.

Caustic Soda and Caustic Potash

Sodium hydroxide (NaOH) and potassium hydroxide (KOH) are both strongly alkaline,

corrosive solids. As chemical re-agents, they are mostly interchangeable, although some

differences exist in specific applications.

1.Chemistry in Air

o Sodium hydroxide, also known as lye or caustic soda, and potassium hydroxide, also

known as caustic potash, are both white solids. They are hygroscopic, meaning they will

absorb water from the air.

Sodium hydroxide will form sodium carbonate (Na₂CO₃, washing soda) by absorption of

carbon dioxide (CO₂):

2 NaOH + CO₂ ‘ Na₂CO₃ + H₂O

Potassium hydroxide, however, will form potassium bicarbonate (KHCO₃):

KOH + CO₂ ‘ KHCO₃

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2. Solubility

o Sodium and potassium hydroxide are strong bases. At room temperature, they exhibit

almost identical solubilities in water – 111 grams of sodium hydroxide will dissolve in 100

millilitres of water vs. 110 grams of potassium hydroxide.

Applications

o Both hydroxides can be used in the saponification of fats to form soap. Soaps prepared

from potassium hydroxide tend to exhibit greater solubility and are commonly referred to as

“soft” soaps.

Manufacture

o Sodium and potassium hydroxides are prepared commercially by electrolysis of sodium

chloride (NaCl, table salt) or potassium chloride (KCl):

2 NaCl + H₂O ‘ H₂ + Cl₂ + NaOH

2 KCl + H₂O ‘ H₂ + Cl₂ + KOH

Differences

o In many applications, potassium and sodium hydroxide can be freely interchanged. The

primary difference between them is cost. In ton quantities, potassium hydroxide is about three

times more expensive than sodium hydroxide.

SEM & TEM

SEM:

SEM involves shooting an electron beam at a specimen and observing the reactions on the

specimen surface. When the electron hits a molecule on the surface, its energy is absorbed by

the molecule, which in turn emits a lower amount of energy. This energy can be in the form

of a secondary, less energetic electron, a photon of light, or x-rays. Differentiation between

these emissions is used to produce image contrast. However, in order to produce a coherent

image, the sample must often be prepared with a conductive coating or by embedding a resin

for many biological samples.

TEM:

TEM acts much like a typical bright field microscope in the sense that it sends electrons

through a specimen. As it propagates through the specimen, some of the electrons are

scattered and some are transmitted. The transmitted electrons is passed through an objective

lens and then projected onto a scintillating material which can then be recorded

photographically. This requires samples to be prepared in very thin slices in order to allow

transmission of the electrons through transparent sections.

OR

A SEM (scanning electron microscope) images using the electrons reflected from a specimen.

A TEM (transmission electron microscope) images using the electrons that pass through it.

The image from an SEM thus looks somewhat like a normal photo (we’re used to imaging

using the light reflected from objects). However, a TEM image takes a bit more interpretation

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as we’re not used to seeing images of light that’s passed through things – think of silhouettes

or slide projectors.

Periscope & Pyrometer:

Periscope:

Instrument used by submarines to see above the surface of the sea.

Pyrometer:

Instrument used for measuring high temperatures.

Cell & Battery

Cell:

A cell is a DC voltage source in which chemical energy is converted into electricity.

Battery:

It is a device which produces electricity through the use of acid and other chemicals. It is

assembly of many cells.

Perimeter & Altimeter

Perimeter:

A perimeter is a path that surrounds an area. The word comes from the Greek peri (around)

and meter (measure). The term may be used either for the path or its length – it can be thought

of as the length of the outline of a shape. The perimeter of a circular area is called

circumference.

Altimeter:

An altimeter is an instrument used to measure the altitude of an object above a fixed level.

The measurement of altitude is called altimetry, which is related to the term bathymetry, the

measurement of depth underwater.

Pelage & Plumage

Pelage:

It is a growth of hair/fur/wool covering the skin of animals.

Plumage:

Plumages are feathers covering the body of birds.

Smog & Smoke

Smog

Smog is formed by the interaction of pollutants present in the air in presence of sun light

(photochemical smog), it usually restricts visibility and is hazardous to health.

Smoke:

Smoke is the thin fine particles usually result from the combustion.

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Radiotherapy & Chemotherapy

1. Radiation targets only the cancer cells. However, chemotherapy is administered through

the blood and therefore, affects both cancerous and non-cancerous cells

2. Though they can be used for any sort of cancer, radiation mainly targets solid tumours like

those of the cervix, spine and skin.

3. Chemotherapy treats cancers through medicines, while radiation deals with cancer cells

through rays

4. Radiation results in additional side effects like internal inflammation, especially in the

stomach and the intestine.

Springtides & Neap tides

Springtide:

i) Spring Tides When the moon is full or new, the gravitational pull of the moon and sun are

combined.

ii) At these times, the high tides are very high and the low tides are very low. This is known

as a spring high tide.

iii) Spring tides are especially strong tides (they do not have anything to do with the season

spring).

iv) They occur when the Earth, the Sun, and the Moon are in a line. The gravitational forces

of the Moon and the Sun both contribute to the tides.

v) Spring tides occur during the full moon and the new moon.

Neap tides:

i) Neap Tides During the moon’s quarter phases the sun and moon work at right angles,

causing the bulges to cancel each other.

ii) The result is a smaller difference between high and low tides and is known as a neap tide.

iii) Neap tides are especially weak tides.

iv) They occur when the gravitational forces of the Moon and the Sun are perpendicular to

one another (with respect to the Earth).

v) Neap tides occur during quarter moon.

Vertebrates & Invertebrates

• Vertebrates have a backbone with a spinal cord, whereas invertebrates do not.

• The diversity is exceptionally high among the invertebrates compared to vertebrates.

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• Vertebrates are always bilaterally symmetrical, while invertebrates could show either

bilateral or radial symmetry.

• Vertebrates are usually large-bodied and move fast compared to invertebrates.

• Vertebrates have a closed blood system, a well-developed brain, either gills or lungs for

respiration, and a complex and sophisticated nervous system, whereas those are primitive in

invertebrates. Therefore, it concerns that vertebrates have many specializations to extract the

best out of the environment compared to invertebrates.

Fluorescent & Neon Light

A neon light is the sort of light you see used in advertising signs. These signs are made of

long, narrow glass tubes, and these tubes are often bent into all sorts of shapes. The tube of a

neon light can spell out a word, for example. These tubes emit light in different colours.

A fluorescent light, on the other hand, is most often a long, straight tube that produces white

light. You see fluorescent lights in offices, stores and some home fixtures.

The idea behind a neon light is simple. Inside the glass tube there is a gas like neon, argon or

krypton at low pressure. At both ends of the tube there are metal electrodes. When you apply

a high voltage to the electrodes, the neon gas ionizes, and electrons flow through the gas.

These electrons excite the neon atoms and cause them to emit light that we can see. Neon

emits red light when energized in this way. Other gases emit other colours.

A fluorescent light works on a similar idea but it has an extra step. Inside a fluorescent light

is low-pressure mercury vapour. When ionized, mercury vapour emits ultraviolet light.

Human eyes are not sensitive to ultraviolet light (although human skin is — see How

Sunburns and Sun Tans Work!). Therefore, the inside of a fluorescent light is coated with a

phosphor. A phosphor is a substance that can accept energy in one form (for example, energy

from a high-speed electron as in a TV tube — see How Television Works) and emit the

energy in the form of visible light. In a fluorescent lamp, the phosphor accepts the energy of

ultraviolet photons and emits visible photons.

The light we see from a fluorescent tube is the light given off by the phosphor that coats the

inside of the tube (the phosphor fluoresces when energized, hence the name). The light of a

neon tube is the colored light that the neon atoms give off directly.

Telemeter:

A telemeter is a device used to remotely measure a quantity. Telemeters are generally the

physical devices used in telemetry. Electronic devices are widely used in telemetry and can

be wireless or hard-wired, analogue or digital. Other technologies are possible, however, such

as mechanical, hydraulic and optical.

Multimeter:

A multimeter or a multi-tester, also known as a VOM (Volt-Ohm meter), is an electronic

measuring instrument that combines several measurement functions in one unit. A typical

multimeter may include features such as the ability to measure voltage, current and

resistance. Multimeters may use analogue or digital circuits—analogue multimeters (AMM)

and digital multimeters (often abbreviated DMM or DVOM.) Analog instruments are usually

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based on a micro-ammeter whose pointer moves over a scale calibrated for all the different

measurements that can be made; digital instruments usually display digits, but may display a

bar of a length proportional to the quantity being measured.

A multimeter can be a hand-held device useful for basic fault finding and field service work

or a bench instrument which can measure to a very high degree of accuracy. They can be

used to troubleshoot electrical problems in a wide array of industrial and household devices

such as electronic equipment, motor controls, domestic appliances, power supplies, and

wiring systems.

Periscope and Microscope

Periscope:

A periscope is an instrument for observation from a concealed position. In its simplest form it

consists of a tube with mirrors at each end set parallel to each other at a 45-degree angle. This

form of periscope, with the addition of two simple lenses, served for observation purposes in

the trenches during World War I. Military personnel also use periscopes in some gun turrets

and in armoured vehicles.

More complex periscopes, using prisms instead of mirrors, and providing magnification,

operate on submarines. The overall design of the classical submarine periscope is very

simple: two telescopes pointed into each other. If the two telescopes have different individual

magnification, the difference between them causes an overall magnification or reduction.

Microscope:

A microscope (from the Greek: μικρός, mikrós, “small” and σκοπεῖν, skopeîn, “to look” or

“see”) is an instrument used to see objects that are too small for the naked eye. The science of

investigating small objects using such an instrument is called microscopy. Microscopic

means invisible to the eye unless aided by a microscope.

There are many types of microscopes, the most common and first to be invented is the optical

microscope which uses light to image the sample. Other major types of microscopes are the

electron microscope (both the transmission electron microscope and the scanning electron

microscope) and the various types of scanning probe microscope.

Nucleon and Photon

Nucleon:

A nucleon is a collective name for two particles: the neutron and the proton. These are the

two constituents of the atomic nucleus. Until the 1960s, the nucleons were thought to be

elementary particles. Now they are known to be composite particles, each made of three

quarks bound together by the so-called strong interaction.

The interaction between two or more nucleons is called inter-nucleon interactions or nuclear

force, which is also ultimately caused by the strong interaction. (Before the discovery of

quarks, the term “strong interaction” referred to just inter-nucleon interactions.)

Photon:

A photon is an elementary particle, the quantum of the electromagnetic interaction and the

basic unit of light and all other forms of electromagnetic. It is also the force carrier for the

electromagnetic force. The effects of this force are easily observable at both the microscopic

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and macroscopic level, because the photon has no rest mass; this allows for interactions at

long distances. Like all elementary particles, photons are currently best explained by quantum

mechanics and will exhibit wave–particle duality, exhibiting properties of both waves and

particles. For example, a single photon may be refracted by a lens or exhibit wave

interference with itself, but also act as a particle giving a definite result when quantitative

momentum (quantized angular momentum) is measured.

Cusec and Comet

Cusec;

Cusec is a measure of flow rate and is informal shorthand for cubic feet per second (28.317

litres per second).

Comet:

A comet is an icy small Solar System body that, when close enough to the Sun, displays a

visible coma (a thin, fuzzy, temporary atmosphere) and sometimes also a tail. These

phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus

of the comet. Comet nuclei range from a few hundred meters to tens of kilometres across and

are composed of loose collections of ice, dust, and small rocky particles. Comets have been

observed since ancient times and have traditionally been considered bad omens.

Telescope and Microscope are two scientific instruments that serve their purposes differently.

One of the main differences between a telescope and a microscope is that a telescope is used

to view things that are far whereas a microscope is used to view things that are very near.

It is indeed true both the instruments are used to watch the minute details of the objects or

things more clearly. Another important difference between telescope and microscope is that

the focal length or the distance from the focal point to the lens is different in these two

scientific instruments.

As a result of this the focal point in the case of a telescope may be at a far off place. On the

other hand the focal point in the case of a microscope is just a fraction of an inch off.

The difference in the diameter of the lens used in the two instruments also matter a lot when

it comes to the difference between them. The lens diameter or the aperture is much larger in a

telescope. This is to ensure that the aperture allows tiny amount of natural light at the focal

point.

On the other hand only artificial illumination is used in a microscope. The artificial

illumination is made to fall at the focal point in a microscope. It is interesting to note that a

telescope and a microscope differ from each other in terms of the curvature of the lens.

A microscope is used to look into smaller details like the structure of the cells and the

unicellular organism. On the other hand larger objects that are very far off are the targets of a

telescope. In short it can be said that a telescope is used to look into space. Magnification is

the keyword in both the scientific instruments.

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Antibiotics and Vaccines

1) Vaccine kills virus while antibiotics kill bacteria.

2) Vaccine is taken once and has permanent effect whereas antibiotics work during the time

of disease.

3) Antibiotics are available in different forms like tablets, capsules, drops or ointments.

Vaccines can be given orally or through injection.

4) Vaccines are preventive method that is taken before getting infected. Antibiotics are taken

after getting infected.

OR

– Vaccines act against most microorganism, whereas antibiotics act against bacteria.

– Vaccines are provided before the manifestation of the infection, but antibiotics are given

mostly after.

– Vaccines usually have a specific single type of microbe, whereas antibiotics would act

against a multitude of species.

– Vaccines enhance the natural immunity, and antibiotics cause destruction of the

biochemistry of the organism.

– Vaccines are highly effective against organism, but there may be resistance to antibiotics

needing the development of newer antibiotics.

– Both have equally lethal complications, but vaccines carry a lesser range of complications

related to antibiotics.

Myopia:

Myopia (short sightedness) is an eye disease in which the patient cannot see the distant

objects clearly. This disease can be corrected by using convex lenses in glasses.

Hyperopia:

Hyperopia (long sightedness) is defect of vision in which a person cannot see the clearly

objects lying close to him. The disease can be corrected by using convex lenses in glasses.

Periscope & Perimeter

Periscope:

Instrument used by submarines to see above the surface of the sea.

Perimeter:

A perimeter is a path that surrounds an area. The word comes from the Greek peri (around)

and meter (measure). The term may be used either for the path or its length – it can be thought

of as the length of the outline of a shape. The perimeter of a circular area is called

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circumference.

X-rays & Gamma Rays

1. Gamma rays cause more harm to human body than the X- rays.

2. Gamma rays have shorter wavelengths than the X-rays.

3. X rays are emitted by the electrons outside the nucleus, and gamma rays are emitted by the

excited nucleus itself.

4. X rays are used in hospitals for taking X-rays but gamma rays are not.

Hydrometer & Hygrometer

Hydrometer

Hydrometer is an instrument used to measure the specific gravity of liquids. It should be

noted that specific gravity is the ration of the density of the liquids to density of water.

Hygrometer:

A hygrometer is an instrument used to measure relative humidity. A simple form of

hygrometer consists of two thermometers, one of which has a dry bulb and the other, a wet

bulb.

Perimeter & Telemeter

Perimeter:

A perimeter is a path that surrounds an area. The word comes from the Greek peri (around)

and meter (measure). The term may be used either for the path or its length – it can be thought

of as the length of the outline of a shape. The perimeter of a circular area is called

circumference.

Telemeter:

A telemeter is a device used to remotely measure a quantity. Telemeters are generally the

physical devices used in telemetry. Electronic devices are widely used in telemetry and can

be wireless or hard-wired, analogue or digital. Other technologies are possible, however, such

as mechanical, hydraulic and optical.

Isotope & Isomer

Isotope:

Isotopes are different types of atoms of same element whose atoms of same element whose

atomic number is same but atomic mass is different. Isotopes have similar chemical

properties but different physical properties.

Isomers:

Isomers are compounds with the same molecular formula but different structural formula.

Isomers do not necessarily share similar properties unless they have same functional groups.

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OR

Isotopes and Isomers

An isotope refers strictly to pure elements. Atoms of the same element that have different

numbers of neutrons in their nuclei are called isotopes. For instance, hydrogen-1 (1H) and

hydrogen-2 (2H or deuterium) are isotopes of each other.

An isomer refers strictly to molecules. Two molecules that have the same composition (i.e.,

the same molecular formula) but are different in the connectivity, shape or orientation, are

called isomers. For instance, n-propanol (1-propanol) and isopropanol (2-propanol or rubbing

alcohol) are isomers of each other. Ethanol is not an isomer of propanol, however, because

they have different formulas.

Flying Mammal & Bird

Flying Mammals:

i. Mammals are the class of animals which give birth to live offspring and feed their young

ones on milk from their breast.

ii.Flying mamma is the type of animal which belongs to mammalian group with additional

quality of flying.

iii.Bats are representative animals of this group.

iii.Bats have many unusual characteristics.

v.They cannot walk very well because of skin that reaches over its front and back legs.

vi. It flies at night and stays in caves and other dark places during the day.

vii.Hanging upside down by the claws of its back legs, it looks like flying mice.

Birds:

i. Birds are winged, bipedal, endothermic warm-blooded, egg laying vertebrate animals.

ii.There are around 10,000 living species across the world.

iii.All birds have fore-limbs modified as wings and most can fly with few exceptions like

ratites, penguins and number of various island species.

Difference between Bats and Birds

The variation between bats and birds is their structure and class. Bats came from the

Chiroptera and Aves family. Bats are webbed structured flying animals while birds are

feathered winged animals. Bats are mammals, so they don‘t lay eggs, compared to birds that

are known as egg-laying animals. When flying, bats don‘t flap their forelimbs completely

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compared to birds. Generally, bats have teeth which help them when eating while birds have

beaks in picking up food and eating them. Bats are nocturnal animals; they hunt and go

around their business at night and sleep during the day while birds work and hunt for food

during daytime and sleep at night.

Typhoons & Tornado

• Hurricane (also called typhoons) is a result of tropical disturbance on a water body, while a

tornado is always formed on land.

• A tropical storm is labelled a hurricane if it takes place between Atlantic and Pacific Ocean,

but the same storm is called a cyclone if it takes place in Indian Ocean.

• Though both have eyes or centre, the centre of a tornado can be huge, extending up to 20

miles in diameter, whereas the eye of a tornado is very small being only a few feet in

diameter

• Hurricanes occur in the months of June to November, whereas Tornados occur in the

months of April to June

• Tornados last for a few minutes or hours, whereas hurricanes can have a very long duration

lasting for 2-3 weeks.

• Thunderstorms are effects of hurricanes, whereas they are the cause of a tornado

• Hurricanes can cause floods and tsunamis, whereas tornados spread epidemics and also

contaminate water sources.

OR

A tornado is a violently rotating column of air extending from the base of a thunderstorm to

the ground. In weather terms tornadoes are small, 50 yards wide on average and rarely

exceeding a mile wide, though on rare occasions tornadoes up to 2.5 miles wide have

occurred. Tornadoes are also short lived, lasting 10 minutes on average, though a few have

lasted for over 3 hours. Tornadoes form from interactions of air currents in a thunderstorm.

Hurricanes and typhoons are essentially the same thing, only a hurricane is in the Atlantic

ocean or north-eastern Pacific ocean while a typhoon is in the north western Pacific ocean.

Both are tropical cyclones with winds of at least 74 mph. In addition to having strong winds

these storms bring heavy rain and flooding. The average hurricane/ typhoon is about 300

miles wide and forms over the course of several days. Unlike tornadoes, which are generally

as land-based event These systems develop from disorganized clusters of thunderstorms that

feed of the moisture from warm ocean water, organize, and intensify.

Microscope & Telescope

Telescope and Microscope are two scientific instruments that serve their purposes differently.

One of the main differences between a telescope and a microscope is that a telescope is used

to view things that are far whereas a microscope is used to view things that are very near.

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It is indeed true both the instruments are used to watch the minute details of the objects or

things more clearly. Another important difference between telescope and microscope is that

the focal length or the distance from the focal point to the lens is different in these two

scientific instruments.

As a result of this the focal point in the case of a telescope may be at a far off place. On the

other hand the focal point in the case of a microscope is just a fraction of an inch off.

The difference in the diameter of the lens used in the two instruments also matter a lot when

it comes to the difference between them. The lens diameter or the aperture is much larger in a

telescope. This is to ensure that the aperture allows tiny amount of natural light at the focal

point.

On the other hand only artificial illumination is used in a microscope. The artificial

illumination is made to fall at the focal point in a microscope. It is interesting to note that a

telescope and a microscope differ from each other in terms of the curvature of the lens.

A microscope is used to look into smaller details like the structure of the cells and the

unicellular organism. On the other hand larger objects that are very far off are the targets of a

telescope. In short it can be said that a telescope is used to look into space. Magnification is

the keyword in both the scientific instruments.

Ultrasonics & Infrasonic:

Ultrasonics:

The study of sound aves with high frequencies beyond the upper limit of human hearing or 20

thousand Hz. This technique is employed to locate a tumour, to scan a pregnant woman‘s

abdomen in order to produce a picture of foetus or to treat certain neurotically disorders.

Infrasonic:

These are the sound waves which have the frequencies lowest than the lowest limits of

human hearing or 20 Hz.

OR

The sounds having frequency more than 20,000 hertz (Hz) are called ultrasonic or ultrasound

and the sounds having frequency less than 20 Hz are called infrasonic or infrasound. Both of

these sounds cannot be heard by human beings. The audible range for of hearing by human

beings is 20 Hz to 20000 Hz.

Antibodies:

Protein synthesized in the blood in response to the entry of foreign substances or organisms into the

body. When the body get infected through virus or bacteria, specific antibody is produced which

fights the disease.

Antibiotics:

These are substances which can stop the growth or destroy the bacteria or other microorganisms. The

antibiotics are used to eliminate fatal diseases such as typhoid, plague and cholera etc.

OR

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Antibodies

l They are what your body produces in response to the presence of antigens (bacterial or viral surface

structures)

l They merely assist your white blood cells in identifying

l They also destroy and invade the unidentified microorganisms.

Antibiotics

l They are chemicals that work to destroy invading bacteria (usually by disrupting the outer cell wall

and making it “leak” or by messing up the bacteria’s metabolic processes. They are not produced by

the body)

l Antibiotics can be antibacterial or antiviral. Antibacterial will only destroy bacteria and antiviral

will only destroy viruses. There are not many antibiotics for viruses. Also a virus is not a eukaryote.

Antigen & Vaccine

Antigen:

A substance or organism that induces the production of an antibody. The antigen reacts with

antibody. The antigen tissue proteins can cause problems in the transplant of organs by rejecting the

introduction of new organ in the body.

An antigen is a foreign molecule that, when introduced into the body, triggers the production of an

antibody by the immune system. The immune system will then kill or neutralize the antigen that is

recognized as a foreign and potentially harmful invader. These invaders can be molecules such as

pollen or cells such as bacteria. The term originally came from antibody generator[1][2] and was a

molecule that binds specifically to an antibody, but the term now also refers to any molecule or

molecular fragment that can be bound by a major histocompatibility complex (MHC) and presented

to a T-cell receptor. “Self” antigens are usually tolerated by the immune system; whereas “Non-self”

antigens are identified as invaders and attacked by the immune system. self-antigens.

Vaccine:

The agent which is used to give immunity against various diseases. A vaccine consists of modified

disease organisms such as live weakened viruses or dead that can induce the production of antibodies

within the blood.

A vaccine is a biological preparation that improves immunity to a particular disease. A vaccine

typically contains an agent that resembles a disease-causing microorganism, and is often made from

weakened or killed forms of the microbe or its toxins. The agent stimulates the body’s immune

system to recognize the agent as foreign, destroy it, and “remember” it, so that the immune system

can more easily recognize and destroy any of these microorganisms that it later encounters.

Vaccines can be prophylactic (example: to prevent or ameliorate the effects of a future infection by

any natural or “wild” pathogen), or therapeutic (e.g. vaccines against cancer are also being

investigated; see cancer vaccine).

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8. Short/Long Notes

Solar System

The solar system is the family of the sun, planets revolving around it, the satellites of the

planets and the asteroids or meteoroids and comets etc.

• There are eight planets in the solar system.

• Starting from the sun there are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and

Neptune.

• All the planets revolve around the sun in their orbits.

• Meteorite analysis shows that the age of solar system is about 4530 million years.

• The sun is not the largest star of the Milky Way; rather it is an average sized star.

• It is not at the centre of the galaxy but shifted towards a side.

• The diameter of the sun is 1, 392, 140 km and its mass is 2 * 1027 tonnes.

• The outermost layer of the sun is called photosphere, has an average temperature of 5570

0C.

• The photosphere rotates at a rate of 25.38 days per turn.

• At the centre of the sun hydrogen is undergoing nuclear fusion reaction which provides

energy for the heat and light so sun.

• The planets of the solar system as well as the moons get light and sometimes heat from the

sun.

• The four inner planets of the solar system are called terrestrial plants because of their rocky

nature.

• The outer planets are called gaseous planets because they don‘t have solid surface and are

composed of gases.

Planets And Their Characteristics:

1. Mercury

• Its distance from Sun is 58 million kms.

• Its revolution period is 88 days.

• Its rotation period is 58 days, 15 hours and 30 minutes.

• It has no moon.

• It is the nearest planet to the sun.

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• It is also the smallest planet of the solar system.

• It is the fastest planet.

• Its radius is 2,433 kms and diameter is 4,878 kms.

• It is covered with holes called Craters.

• It has no atmosphere.

• The temperature on mercury vary between 420 0C (7900F) in the day and -180 0C (-2900F) at

nights.

2. Venus

Apart from the moon, Venus is the brightest object in the sky. Venus can be seen with naked eye

in the morning or in the evening. Following are the main characteristics of the Venus.

• Its distance from the Sun is 108 million kms.

• Its revolution period is 224.7/225 days.

• Its rotation period is 243 days and 14 hours (longest day)

• It has no moon.

• It is the nearest neighbour of the earth in the solar system.

• It is the brightest planet.

• It is also the hottest planet.

• Its diameter is 12,102 kms.

• It is wrapped in thick clouds of CO2 gas.

• It rotates from east to west as opposite to most other planets.

3. Earth

The earth is the largest and the densest of the four terrestrial planets. It is the most wonderful

planet of the solar system. Following are the features of the Earth.

• Its distance from the Sun is 150 million kms.

• Its revolution period is 365 ¼ days.

• Its rotation period is 23 hours, 56 minutes, 40 seconds.

• It has one moon.

• It is the densest planet.

• It is also the watery and bios planet.

• Its diameter is 12756 km (7927 miles equatorial and 7900 miles polar diameter)

• It has atmosphere which contains 78% Nitrogen, and 21% Oxygen.

• Its two-thirds surface is covered with oceans.

• The earth‘s surface is rich in Oxygen, Silicon, Aluminium, Iron, Calcium, Sodium etc.

4. Mars

• Distance form sun 228 million kms.

• Revolution period 687 days.

• Rotation period 24 h, 37 min and 22 sec.

• It has two moons Phobos and Deimos.

• Its diameter is 6794 kms.

• Mars is covered with red dust.

• It has an atmosphere composed almost entirely of CO2.

• Its average temperature is -53 0C.

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5. Jupiter

• Its distance from sun is 778 million kms.

• Revolution period 12 years.

• Rotation period 9h, 50min, and 30 sec. (smallest day)

• It has 63 moons.

• It is the largest planet of the solar system.

• It has the largest number of satellites.

• Its diameter is 1, 24,800 kms.

• Its diameter is eleven times greater than the earth‘s diameter.

• It has a dense, cloudy atmosphere of hydrogen and helium.

• It has a rock-iron-ice core about 15, 000 km (9,000 miles) thick.

• Jupiter radiates 67% more heat than it receives from the sun. this is mainly due to dissipation of

the primordial heat of the planet.

6. Saturn

In 1610, Galileo became the first person to look at Saturn through telescope.

• Distance from Sun 1427 million kms.

• Revolution period 30 years.

• Rotation period 10h, 14 mins.

• It has 62 moons.

• The largest moon of Saturn is the Titan and it is the second-largest moon in the solar system.

Titan is larger than the planet Mercury.

• It is the second largest planet.

• It has a magnificent system of rings.

• Its diameter is 1, 20, 000 km.

7. Uranus

When sky is very dark and very clear Uranus can be seen with the naked eyes. The planet was

discovered by William Herschel in March 1787.

• Its distance from Sun is 2869.9 million kms.

• Revolution period is 84 years.

• Rotation period is 16h, and 10 mins.

• It has 27 moons.

• Titania is the largest moon of Uranus.

• It has an atmosphere which is dominated by hydrogen and helium.

• Its diameter is 52, 400 km.

8. Neptune

Neptune was discovered by the German astronomer Johann Galle.

• Distance from Sun 4496, 6 million kms.

• Revolution period 165 years (largest year)

• Rotation period 18 hours.

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• Neptune has 13 moons that we know of. The largest moon is Triton.

• It is the coldest planet.

• It is the slowest to move around the sun.

• Its diameter is 49,100 kms.

• It is known as the twin of Uranus due to their similarity of size, mass and composition.

Short Note (Solar System)

Lunar Eclipse:

The partial or complete obscuration of light of moon for an observer on the earth is called lunar

eclipse.

Lunar eclipse takes place when the earth comes in position between the sun and the moon. In this

way, the shadow of the earth is cast on the moon and the moon does not get sunlight in this

position.

Lunar eclipse occurs only when there is full moon. But this does not happen on every full moon

because of inclination of the axis of earth to its orbit.

Solar Eclipse:

Solar eclipse occurs when the moon comes in between the Sun and the earth and its shadow is

cast across the face of the earth.

The solar eclipse occurs when the moon moves to a position between the Sun and the Earth.

During this process it throws shadow on the earth. This shadow is categorized in umbral and

penumbra. The people who are in the umbral region are unable to see the sun at all. This

condition is known as the total eclipse of the sun. While the people in penumbra region can see

the sun partly this is known as the partial eclipse of the sun.

This happens with the new moon when the moon is in conjunction with the sun. this does not

happen at every new moon because of the inclination of the orbit of the moon to the orbit of earth

around the sun.

Asteroids:

Asteroids are also known as planetoids. These are small, irregularly shaped rocky objects which

orbit the Sun between the orbits of Mars and Jupiter. Asteroids are also known as the minor

planets.

Basically the word Asteroid means ―Starlike‖. Ceres asteroid was the first to be discovered.

Meteorites:

Meteorites are small chunks of iron and rock thought to be resulted from collisions between

asteroids. They also may be formed when comets disintegrate into fragments. Meteorites enter the

earth‘s atmosphere and become a meteor. A meteor is a ―falling star‖ that is usually seen in the

sky at night. A meteor will burn up from frictional heating as it enters the atmosphere. Most of

the meteors burn up before they reach the earth. If they do not reach the ground they become

meteorites. Meteorites can be seen at a distance of 70 miles from the earth. Meteorites are heavy

objects which weigh about 60 tons.

Comets:

Comets are those bodies which revolve round the sun. they are mainly composed of ice and dust.

Most comets have three parts which are as under.

i) A solid centre.

ii) A head or round coma, that surrounds the centre and consists of dust particles mixed with

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frozen water, frozen methane and frozen water, frozen methane and frozen ammonia.

iii) A long tail of dust and gases that escape from the head. Most comets stay near the solar

system.

Other characteristics of comets are as under:

• Comet is usually about 10 km or 6 miles across.

• Comets are usually made up of ice and dust.

• Millions of comets are present in the solar system.

• Halley‘s comet is the famous example.

• Comets usually move around the sun in the elliptical orbits.

Light Year:

The distance travelled by light at speed of 186,000 miles per seconds in one year is known as a

light year. One light year is approximately 9461,000 million kilometres or 5875000 miles. Light

year is also used to measure the distance between the galaxies.

Astronomical Unit:

The distance between the Sun and the Earth is called as Astronomical Unit. This unit is also used

in the measurement of distances between the heavenly bodies within the solar system. The earth

is one A.U away from the Sun and the Pluto is 39 A.U away from the Earth.

Black hole:

Black Hole is a hypothetical region in space which has a big gravitational pull for which no

matter or radiation can escape from it. Even it is believed that light cannot escape from it. Black

Hole usually likes at the centre of galaxy.

Super Nova:

A Super Nova is an exploding star. At the end of its phase as a Red Giant, a heavy star explodes

as a Supernova shining briefly as brightly as a thousand million stars. Recent Supernova was

observed on the night of Feb 23, 1987. This occurred in Large Magellanic Cloud.

Nebula:

Nebula is derived from a Greek word which means ―Cloud‖. In the sky there are clouds like

objects, which are classified as Nebulae. There are both luminous diffuse nebulae and dark

obscuring nebulae over the Milky Way. They are made up of dust and gases.

Aurora:

Aurora or Kutub-i-Raushani is a luminous meteoric phenomenon of electrical character seen in

Polar Regions with a tremulous motion and giving forth streams of eight Aurora. It is generally

believed that the aurora is actually caused by radiation from the Sun-spots.

Solar Wind:

Solar wind is the stream of electrically charged particles especially protons and electrons, which

are emitted by the Sun, predominantly during solar flares and sunspots activity. Some of these

particles become trapped in the Earth‘s magnetic field forming the outer Van Allen radiation belt,

but some penetrate into the upper atmosphere where they congregate in narrow zones in the

region of the Earth‘s magnetic poles producing aurora displays.

Cosmic Rays:

Cosmic Rays are charged particles moving as fast as the speed of light. Most of the particles are

protons, while some are alpha particles and electrons. They travel throughout our galaxy,

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including the solar system and some strike the earth‘s atmosphere. They can be detected by

instruments on the Earth. Nobody knows how cosmic rays are formed. Some of them are formed

by exploding stars or supernova and some come from outside our Galaxy.

Some Important Definitions:

Cosmology:

Cosmology is the science of the cosmos or universe.

OR

Cosmology is the branch of physical science which deals with the Universe.

Universe:

The universe is the sum total of all that exists, or has existed, both in space and time.

Galaxy:

A galaxy is a system of many thousands of millions of stars together with inter-stellar gas and

dust.

OR

Galaxy is a fundamental unit of the universe. It is composed of hundreds of thousands of stars

together with intra-stellar gas and dust.

Star:

Those heavenly bodies which are luminous and produce their own energy by nuclear reactions

are called stars.

• Proximal Centauri second nearest after Sun to the Earth.

• Antares is one of the largest stars known.

Solar system:

A tiny system of our galaxy which consists of the /sun, a planet and their satellites, thousands of

miniature planets called asteroids, meteoroids, comets, interplanetary dust and plasma.

Satellite:

Those heavenly bodies which revolve round the planets are called satellites.

Eclipse:

In astronomy, the term eclipse simply means the obscuring of one heavenly body by another,

particularly that of the sun or a planetary satellite.

Lunar Eclipse:

A condition when the earth comes in between the sun and the moon and throws its shadow on the

moon is called lunar eclipse.

Solar Eclipse:

A condition when the moon comes in between the sun and the moon and throws its shadow on

the moon is called Solar Eclipse.

Astrology:

Astrology is the interpretation of the influence of planets and stars on human lives.

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Asteroids:

Small, irregular shaped rocky objects which orbit the sun between the orbits of Mars and Jupiter

are called Asteroids.

Meteorites:

Tiny chunk of material floating in space which can also enter the earth‘s atmosphere and become

meteor are known as meteorites.

Comets:

The bodies mainly composed of ice and dust which revolve round the sun are called comets.

Balanced Diet:

• ―The food which contains all essential food nutrients which are necessary and essential for

healthy growth of the body and proper functioning of the whole parts of body.‖

• Food is a complex mixture of chemical substances.

• It performs following useful functions when eaten and absorbed by the body.

i) Produces energy

ii) Promote growth

iii) Repair the tissues

iv) Regulate various processes

• Nutrients are the chemical components of food capable of performing above functions.

• Example: milk is a balanced diet although it does not contain iron.

• Following are the major components of Balanced Diet and their source and functions:

i) Carbohydrates

Source: Honey, Sugarcane, Wheat, Maize, Potatoes.

Functions: Provide energy

ii) Fats:

Source: Butter, Cheese, Soya bean, Mustard etc.

Functions: Provide Energy

iii) Proteins:

Source: Meat, Eggs, Fish, Milk, Pulses etc.

Functions: Essential for growth

iv) Vitamins:

Source: Fruits and Vegetables.

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Functions: Important for proper physiologic and metabolic functions of the body.

Types:

a) Water Soluble Vitamins: B1, B2, B6, B12, C

b) Fat Soluble vitamins: A, D, E, K

v) Minerals: Minerals are those inorganic substances which play a key role in the maintenance

and building of the body tissues. The most important minerals of balanced diet are as under:

Phosphorus: is necessary for bones and teeth.

Iron: is an essential component of blood.

Iodine: is necessary for thyroxin which is secreted from thyroid gland.

Calcium: is necessary for bone development.

vi) Water:

Source: Fruits, Vegetables

Functions: It is constituent of blood, lymph, hormones and other secretions of the body.

Functions Of Vitamins:

1. Vitamin A

i) Role: Vitamin A plays an important role in growth and body repair, keeps the skin smooth and

essential for vision.

ii) Deficiency: it deficiency causes ―Night Blindness‖.

iii) Source: Fortified milk, butter, eggs, cream, leafy vegetables, carrot.

2. Vitamin B1

i) Role: it is an energy building vitamin, help in the digestion of carbohydrates, keep the heart

and muscle stable and necessary for nerves.

ii) Deficiency: its deficiency causes Beri Beri, muscular weakness, cramps and heart swelling.

iii) Source: Pork, cereals, legumes, nuts and seeds.

3. Vitamin B2 (Riboflavin)

i) Role: It is important in forming RBCs, protection of mouth and mucous membrane and skin.

ii) Deficiency: its deficiency causes ―Pellagra‖

iii) Source: Milk, leafy green vegetables, cereals etc.

4. Vitamin B3 (Niacin)

i) Role: Helps in releasing energy from carbohydrates, fats and proteins, very essential for the

DNA synthesis, used to lower elevated LDL cholesterol and triglyceride levels in the blood,

boosts the level of HDL, the ‘good’ cholesterol, in the body, essential for the proper digestion of

the food etc.

ii) Deficiency: its deficiency causes Loss of appetite, Indigestion, Skin lesions, Mental imbalance

etc.

iii) Source: Meat, poultry, fish, cereals, vegetables, peanuts, butter etc.

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5. Vitamin B6 (Pyridoxine)

i) Role: it is essential for the production of antibodies, for the CNS and help in protein

metabolism in the body.

ii) Deficiency: Skin problems, Nervous system disorders, Muscle spasms, Sleeplessness.

iii) Source: Meat, fish, poultry, vegetables, fruits etc.

6. Vitamin B12 (Cynocobalamin)

i) Role: it is important for carbohydrate and fat metabolism, growth of child and formation of

blood.

ii) Deficiency: its deficiency causes ―anaemia‖

iii) Source: Meat, poultry, fish, seafood, eggs, milk.

7. Vitamin C (Ascorbic Acid)

i) Role: It is essential for protection of bones and for healthy teeth and gums.

ii) Deficiency: its deficiency causes ―Scurvy‖

iii) Source: Citrus fruit, guava, pineapple, tomatoes, spinach, turnips, strawberry.

8. Vitamin D:

i) Role: It is very important for the growth of children.

ii) Deficiency: Its deficiency causes ―Rickets‖ in children and Osteoporosis in adults.

iii) Source: Egg yolk, liver, fish, milk.

9. Vitamin E:

i) Role: it plays an important role in wound healing, prevention of sterility, breaking blood clots

and prevents damage of cells due to aging.

ii) Source: Leafy green vegetables, soya bean, cotton seed, liver, egg yolk, nuts etc.

iii) Deficiency: its deficiency slows down the formation of RBCs.

10. Vitamin K:

i) Role: essential for blood clotting.

ii) Deficiency: its deficiency causes ―Blood clotting Disorder‖

iii) Source: Leafy green vegetables, milk, fish, liver, alfalfa.

Minerals: Their Functions, Source and Sings Of Deficiency:

1. Calcium:

i) Role:

a) It is essential constituent of bones and teeth.

b) It is vital for metabolic process such as nerve function, muscle contraction, and blood clotting.

ii) Source: Dairy Products

iii) Deficiency: Osteomalacia (softening of bones), Osteoporosis, Rickets, Tetany

2. Iron:

i) Role: It is the key constituent of haemoglobin which helps in transfer of oxygen.

ii) Source: Eggs, Green Vegetables, Fortified foods, Cereals, White flour, Liver, Meat, Nuts,

Peas.

iii) Deficiency: Anaemia, Increased susceptibility to infection.

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3. Magnesium:

i) Role: it is essential for healthy bones; muscles and nervous tissues. It is needed for functioning

of approx. 90 enzymes.

ii) Source: Eggs, leafy vegetables, fish, milk and dairy products.

iii) Deficiency: Anxiety, fatigue, insomnia, muscle problem, nausea, premenstrual problem.

4. Phosphorus:

i) Role: it is important for healthy bone tissues.

ii) Source: Dairy products, fruits, meat, pulses, leafy vegetables.

iii) Deficiency: Anaemia, demineralization of bones, nerve disorder, respirator problem,

weakness, weight loss.

5. Potassium:

i) Role: it is essential for intracellular fluid, maintenance of electrical potential of the nervous

system and functioning of muscle and nerve tissues.

ii) Source: Cereals, coffee, fresh fruits, meat, vegetables, whole-grains, flour.

iii) Deficiency: General muscle paralysis and metabolic disorder.

6. Sodium:

i) Role: it is necessary for the control of the volume of extra cellular fluid in the body

maintenance of pH of the body, and electrical potentials of the nervous system.

ii) Source: Bakery products, Table salts

iii) Deficiency: Low blood pressure, general muscle weakness, respiratory problems.

Computer:

“The word Computer is derived from compute which means to calculate. In simple and

technical term it is an automatic electronic calculating machine that processes or

manipulates a given data according to a program or set of instructions and gives a desired

output.”

Parts Of A Computer:

The computer is composed of two parts:

1) Hardware

2) Software

1) Hardware:

All physical components of computer, which can be touched, measured, have weight and occupy

space, are collectively called computer hardware viz;

i) Keyboard

ii) Mouse

iii) Joy stick

iv) Scanners

v) Monitor

vi) Printer

vii) Central Processing unit etc.

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2) Software:

Software can be defined as a set of instructions or codes written in a defined manner. In other

words softwares are prewritten programs, which control the operations of computer.

OR

All programs and data stored on floppy disk, Hard disk, CD-ROM are collectively called

softwares. Examples are;

i) DOS

ii) Window

iii) UNIX

iv) XENIX

v) Linus

vi) Java

vii) MS Office

Devices OR Components Of A Computer:

The computer is a combination of many parts, each of which performs specific task

independently. The major devices of a computer are as under.

1) Input Devices

The input devices are those devices which send data or information to the Central Processing

Unit. The main input devices are:

i) KEYBORD: It is used to enter text. It contains alphabetic, numeric and other keys for entering

data.

ii) MOUSE:It is a pointing device. It controls the pointer on the screen.

iii) MICROPHON: It is used to enter voice into the computer.

iv) SCANNER: It reads printed text and graphics and then translates the result into digital form.

v) DIGITAL CAMERA:It is used to take photos.

vi) PC CAMERA: It is used to create movie and to take photos on the computer.

2) OUT PUT DEVICES:

A hardware component used to display information to the user output device.

i) MONITER: It is used to display text, graphics and video output.

ii) PRINTER: It is used to display printed output on paper.

iii) SPEAKER:It is used to hear sound to hear sound music and voice outputs.

3) STORAGE DEVICE:

The hardware components used to store data, instructions and information permanently are called

storage devices. For example floppy disk drive, zip drive, hard disk drive, CD-ROM drives etc.

4) COMMUNICATION DEVICES:

It is used to communicate and exchange data, instructions and information with other computers.

For example Modem.

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UNITS OF CPU:

ALU(ARTHMETIC AND LOGICAL UNIT)

ALU is a part of CPU. Actual execution of instructions takes place in this part. All arithmetic and

logical operations are performed in ALU. It consists of two units:

1. Arithmetic Unit

It performs basic arithmetic functions such as addition, subtraction, division.

2. Logical Unit

It performs logical operations like comparing two data items to find which data item is greater

than, equal to, or less than the other.

CONTROL UNIT

It acts like a supervisor of the computer. It does not execute program instruction by itself. It

controls and coordinates all activities of computer system.

Memory Unit (MU)

It is responsible for storage of data and information. The memory unit consists of two types of

memory which are RAM and ROM.

Some Important Definitions And Short Notes:

RAM:

RAM stands for random access memory. It is that part of CPU where temporary information is

stored.

Byte:

A group of 8 bits is called a byte.

Icons:

Pictorial objects on the desktop or screen are called Icons.

Mouse:

It is an input device, normally called a ―Pointing device‖. This device is used for pointing

anything on monitor through a blinking cursor.

Software:

A set of instructions or codes written in a defined manner or prewritten programs which control

the operations of computer.

Control Unit:

A unit of CPU which is responsible for all automatic operations carried out by the digital

computers is called CU. The CU directs and coordinates all activities of a computer.

LAN:

LAN stands for local area network. It is privately owned communication network that serves

users within a confirmed geographical area. The range is usually within a mile-perhaps one

office, one building or a group of buildings.

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WAN:

It stands for wide area network. It is a communication network that covers a wide geographical

area. The range is usually a state or a country. Examples are Telenet, Uninet etc.

Modem:

Modem is abbreviation of Modulate-de-Modulate. Modulation is a process that converts digital

signals into Analog form and Demodulation is a process that converts Analog signals into digital

form. The device which performs modulation and demodulation is called a MODEM. In simple

words it is a device that converts the digital signals into Analog and then back from Analog to

digital form.

ALU:

A unit of CPU that performs arithmetic and logical operations is called ALU.

Register:

Registers are high-speed staging areas that temporarily store data during processing and provide

working areas for computation.

Registers are contained in control unit and arithmetic Logic Unit. Following are the major types

of registers:

i) Address Register

ii) Instructions Register

iii) Storage Register

iv) Accumulator Register

Soft Copy:

It displays the data on screen of monitor. It can be carried in a floppy disk. A change can be made

in a soft copy.

Hard Copy:

The data is printed on paper card etc. with the help of printer. It cannot be carried in a floppy

disk. No change can be made in hard copy.

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Energy:

Definition Of Energy:

―Energy is an agent which is responsible to do work.‖

OR

―The capacity or ability of doing some work is known as energy.‖

Kinds OR Types Of Energy:

i) Kinetic energy: The energy due to motion of a body is called Kinetic Energy.

Example: i) Moving ball can break a glass window ii) A striking hammer can drive a nail.

ii) Potential Energy: the energy which is possessed by a body by means of its position is known

as potential energy.

iii) Mechanical Energy: Energy of an object due to its motion or position

OR

A combination of kinetic and potential energy resulting from the force of gravity or the

movement or release of a machine component, such as a spring, clamp, or wheel.

iv) Chemical energy: energy in a substance that can be released by a chemical reaction. For

example: coal, petroleum are the source of chemical energy.

v) Electrical energy: energy made available by the flow of electric charge through a conductor.

vi) Heat energy: a form of energy that is transferred by a difference in temperature.

vii) Solar energy: Radiant energy emitted by the sun.

viii) Hydropower energy: The energy in flowing water is called Hydropower Energy.

ix) Nuclear energy: The energy released by a nuclear reaction, especially by fission or fusion.

Energy Resources:

Energy resources can be divided into two categories.

1) Renewable Resources Of energy

2) Non-Renewable Resources Of energy

Renewable Resources Of Energy:

Renewable energy is energy which is generated from natural sources i.e. sun, wind, rain, tides

and can be generated again and again as and when required. They are available in plenty and by

far most the cleanest sources of energy available on this planet. For e.g.: Energy that we receive

from the sun can be used to generate electricity. Similarly, energy from wind, geothermal,

biomass from plants, tides can be used this form of energy to another form.

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OR

The resources of energy which can be used again and again are known as renewable resources.

These are:

i) Solar energy: Solar energy is the energy derived from the sun through the form of solar

radiation.

ii) Wind energy: Wind power is the conversion of wind energy into a useful form of energy,

such as using wind turbines to make electricity, wind mills…

iii) Hydropower energy: Energy in water can be harnessed and used. Since water is about 800

times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield

considerable amounts of energy.

iv) Tidal energy: Tidal power, also called tidal energy, is a form of hydropower that converts the

energy of tides into useful forms of power – mainly electricity.

v) Geothermal energy: Geothermal energy is power extracted from heat stored under the earth‘s

crust. This power source is generally cost effective, usually reliable, mostly sustainable, and

generally environmentally friendly.

Non-Renewable Resources Of Energy:

Renewable energy is energy which is taken from the sources that are available on the earth in

limited quantity and will vanish fifty-sixty years from now. Non-renewable sources are not

environmental friendly and can have serious effect on our health. They are called non-renewable

because they can be re-generated within a short span of time. Non-renewable sources exist in the

form of fossil fuels, natural gas, oil and coal.

OR

The resources of energy which can be used for a particular period of time, after that they may not

be available for the use of man. These include:

i) Coal: Coal is a combustible black or brownish-black sedimentary rock formed from fossilized

plants. Coal consists of amorphous carbon with various organic and some inorganic compounds

and is normally occurring in rock strata in layers or veins called coal beds.

ii) Gas: Natural gas is a combustible mixture of hydrocarbon gases that occurs with petroleum

deposits consisting primarily of methane. It is found with other fossil fuels and in coal beds and is

created by the decay of methanogenic organisms in marshes, bogs, and landfills. Lower

temperatures are likely to produce more petroleum, and higher temperatures are likely to produce

more natural gas.

iii) Oil: Petroleum, also known as crude oil, is a naturally occurring toxic combustible liquid

primarily made up of hydrocarbons. Petroleum is the result of partial decay of living organisms

occurring in the rock strata of certain geological formations.

iv) Nuclear fuels: Nuclear power is produced by controlled nuclear fission (splitting atoms). In

most cases nuclear power plants use nuclear fission reactions to heat water, using the steam to

produce electricity. Uranium, specifically, uranium -235, is one of the few elements easily

fissioned.

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v) Wood: Wood and wood products used as fuel, including round wood (cord wood), limb wood,

wood chips, bark, sawdust, forest residues, charcoal, pulp waste, and spent pulping liquor.

Non-Conventional Sources Of Energy:

Non-conventional sources of energy are those sources of energy which are not in common use at

this time but are being considered or explored to bring to routine use in the future. With the

exhaustion of conventional sources of energy the search for non-conventional sources of energy

have been intensified.

Conventional sources of energy are coal, gas, oil, wood and nuclear fuels. These sources are in

routine use nowadays.

Non-conventional sources of energy are solar energy, geothermal energy. Wind energy, tidal

energy and ocean thermal gradient.

Solar Energy:

The energy of the sun is called solar energy. It has been estimated that on the average 180,000

kilowatts solar energy is falling per square kilometre of the earth. Solar energy is utilized in two

ways.

A solar furnace contains thousands of mirrors to focus the sun rays. In this solar heater produces

heat used in industry or houses. The heaters heat up water or air. Solar energy can also be used

indirectly. Solar cells made up of panels of semi-conductors (usually silicon) are used which

when illuminated by sun generate electricity. These kinds of cells have frequently been used in

space probe. They have not become popular in domestic side due to high cost.

Wind Energy:

Energy obtained from wind by using wind mills is called wind energy. The wind rotates

generated which produce electricity.

Previously wind mills were used for grinding grains. The rotating wings of a wind mill can be

attached to a magnet which gives an electric current with rotation. Low power, high cost and

uncertainties of weather had not made power generation through wind power.

Geothermal energy:

Heat energy obtained from the hot molten metals inside the earth crust serves as the source of

thermal energy. This type of energy is present in the form of hot water and steam. Geothermal

electricity plants change the geothermal energy into electricity. Hot water of springs is being used

for power generation particularly in USA, Italy, and Japan etc. furthermore; hot springs are used

as geysers for heating the houses.

Nuclear Energy:

The most concentrated form of energy is in the atomic nuclei. This energy can be released by the

processes of fission or fusion.

Fusion reactions have been producing electricity in commercial quantities for about 30 years. In

Pakistan we have got only one fission nuclear reactor located at Karachi which generates 137

megawatt of power to meet ur future domestic and industrial needs, we will have to generate

electricity from nuclear plants using (Uranium U-235) and plutonium s fuel.

Tidal Energy:

Energy which is obtained through the tidal waves of the sea is called tidal energy. Tidal waves of

sea strike the shore constantly. These waves are used to run electric generators which produce

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electricity. The kinetic energy of the tides is also used to produce other forms of mechanical

work. Tidal power station traps high tides behind a barrage. The water flows through turbines.

Greenhouse Effect:

The heating that occurs when gases such as carbon dioxide trap heat escaping from the Earth

and radiate it back to the surface; so-called because the gases are transparent to sunlight but

not to heat and thus act like the glass in a greenhouse.

OR

The overall warming of the earth’s lower atmosphere primarily due to carbon dioxide and

water vapour which permit the sun’s rays to heat the earth, but then restrict some heat-energy

from escaping back into space.

Greenhouse Gases:

i) Carbon dioxide CO2

ii) Methane

iii) Water Vapour

iv) Chloro Fluoro-Carbon (CFC)

v) Nitrous oxide

Mechanism OF Greenhouse Effects:

• Our Earth receives most of its energy, called radiation, from the Sun.

• This energy is electromagnetic radiation in the form of Visible light, with small amounts of

Infrared (IR) and Ultraviolet (UV).

• The incoming Visible solar energy has a very short wavelength and passes right through the

atmosphere.

• The Earth’s surface absorbs the solar energy and releases it back to the atmosphere as

Infrared (IR) radiation, some of which goes right back into space.

• But some of the IR radiation emitted by the Earth is absorbed by greenhouse gases in the

atmosphere and sent back towards the Earth’s surface.

• That warms the Earth’s surface. Three main gases in our atmosphere that contribute to the

greenhouse effect are carbon dioxide, methane, and water.

• These gases absorb the infrared radiation emitted by the Earth and re-radiate the energy as

heat back towards the Earth, causing a warming known as the greenhouse effect.

• The warming due to greenhouse gases is expected to increase as humans add more

greenhouse gases to the atmosphere.

Sources Of Greenhouse Gases:

Carbon dioxide (CO2) is a colourless gas that’s a by-product of the combustion of organic

matter. Today human activities are pumping huge amounts of CO2 into the atmosphere,

resulting in an overall increase in carbon dioxide concentrations.

Methane occurs naturally when organic material decomposes. Man-made processes produce

methane in several ways:

• By extracting it from coal

• From large herds of livestock (i.e., digestive gases)

• From the bacteria in rice paddies

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• Decomposition of garbage in landfills

Importance Of Greenhouse Effect:

Following is the importance of greenhouse effect.

i) Without greenhouse effect, the Earth would not be warm enough for humans to live.

ii) Without greenhouse gases, heat would escape back into space and Earth‘s average

temperature would be about 600 F colder.

Global Warming:

A gradual increase in the overall temperature of the earth’s atmosphere generally attributed to the

greenhouse effect caused by increased levels of carbon dioxide, CFCs, and other pollutants

Causes Of Global Warming:

The main causes of global warming, in order of the magnitude of their impact, are:

1. Carbon Dioxide from:

A. Fossil Fuel

B. Deforestation

C. Failing Sinks

2. Methane from:

A. Cattle and Rice Paddies

B. the Arctic Tundra

C. Clathrates

3. Nitrogen Oxides from Farming

4. Other Gases

Effects OF Global Warming:

When it comes to global warming, harmful effects like melting polar ice caps, weather changes,

and an increase in diseases are changing the world and will ultimately affect your life. Below is

the list of effects that global warming is having on environment, climate and human kind.

1. Melting of glaciers: The melting of glaciers will create plethora of problems for human kind

and the animals living in the earth. Due to increased global warming, the level of the sea will rise

which will lead to flooding and this will in turn create havoc in human life. Apart from raising the

sea levels, it will also endanger several species of animals and thus will hamper the balance of the

ecosystem. Moreover these large glaciers reflect light back into the space and with meltdown of

these glaciers, earth will be further warmed.

2. Climate Change: Irregular weather patterns have already started showing results. Increased

precipitation in the form of rain has already been noticed in polar and sub Polar Regions. More

global warming will lead to more evaporation which will cause more rains. Animals and plants

cannot easily adapt to increase rainfall. Plants may die due to it and animals may migrate to other

areas, which can cause entire ecosystem out of balance.

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3. Droughts: Large scale evaporation will be the major cause of droughts in many places

particularly Africa. Although, it is reeling under the huge pressure of water crisis, increased

global warming would further make the situation worse and will cause malnutrition.

4. Diseases: As the temperature becomes warmer, it will have an effect on the health of humans

and the diseases they are exposed to. With the increase in the rainfall, water borne diseases are

likely to spread specially malaria. The earth will become warmer and as a result heat waves are

likely to increase that will cause a major blow to the people particularly in Europe.

5. Hurricanes frequency: As the temperature of the oceans rises, hurricanes and other storms are

likely to become stronger. With the increase in the global warming the water in the ocean warms

up and it heats up the surrounding air, creating hurricanes. More water evaporation means more

hurricanes.

6. Agriculture: Global warming will affect agriculture. Although the results are not visible yet,

but it may show its colours in years to come. As the global temperature will increase plants will

find it harder to survive and will die. Plants are the major source of food for human beings and as

a result food shortage will occur. The shortage of the food may lead to war and conflicts in some

countries.

Steps To Control Global Warming:

i) Use Public Transport:

ii) Use Renewable Energy Like Wind Power:

iii) Burn Methane:

iv) Use Smart Cooler, Heater & Air Conditioner

v) Tune up and maintain vehicles properly

vi) Reduce electricity usage to the maximum

vii) Prefer recycling.

Ozone Depletion:

Ozone:

Ozone is a highly reactive and unstable gas, which is formed by the recombination of oxygen

(O2) atoms in the presence of intense radiation. Its symbol is O3.

Ozone Layer:

The ozone layer is a naturally occurring zone found in the stratosphere, situated between 10-

15 kms above the surface of the Earth. The main function of the ozone layer is to act as a

shield against ultraviolet (UV) radiations from the Sun because these rays are harmful to life.

Ozone Depletion:

Destruction of the stratospheric ozone layer which shields the earth from ultraviolet radiation

harmful to life. …

Causes Of Ozone Layer Depletion:

The Main Ozone-Depleting Substances (ODS)

• Chlorofluorocarbons (CFCs)

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• The most widely used ODS, accounting for over 80% of total stratospheric ozone depletion.

• Used as coolants in refrigerators, freezers and air conditioners in buildings and cars

manufactured before 1995.

• Found in industrial solvents, dry-cleaning agents and hospital sterilants.

• Also used in foam products — such as soft-foam padding (e.g. cushions and mattresses) and

rigid foam (e.g. home insulation).

• Halons

• Used in some fire extinguishers, in cases where materials and equipment would be

destroyed by water or other fire extinguisher chemicals. In B.C., halons cause greater damage

to the ozone layer than do CFCs from automobile air conditioners.

• Methyl Chloroform

• Used mainly in industry — for vapour degreasing, some aerosols, cold cleaning, adhesives

and chemical processing.

• Carbon Tetrachloride

• Used in solvents and some fire extinguishers.

• Hydro fluorocarbons (HCFCs)

• HCFCs have become major, ―transitional‖ substitutes for CFCs. They are much less

harmful to stratospheric ozone than CFCs are. But HCFCs they still cause some ozone

destruction and are potent greenhouse gases.

OR

The cause of ozone depletion is the increase in the level of free radicals such as hydroxyl radicals,

nitric oxide radicals and atomic chlorine and bromine. The most important compound, which

accounts for almost 80% of the total depletion of ozone in the stratosphere are

chlorofluorocarbons (CFC). These compounds are very stable in the lower atmosphere of the

Earth, but in the stratosphere, they break down to release a free chlorine atom due to ultraviolet

radiation. A free chlorine atom reacts with an ozone molecule (O3) and forms chlorine monoxide

(ClO) and a molecule of oxygen. Now chlorine monoxide reacts with an ozone molecule to form

a chlorine atom and two molecules of oxygen. The free chlorine molecule again reacts with ozone

to form chlorine monoxide. The process continues and the result is the reduction or depletion of

ozone in the stratosphere.

Effects Of Ozone Depletion

Following are the major effects of ozone layer depletion.

i) It will increase the risk of skin cancer

ii) It has resulted in melanomas, a kind of tumour.

iii) It greatly affects eyes and produces disease of vision.

iv) It suppresses immunity system of human beings.

v) UV rays damage various crops.

vi) It kills plankton and fish larvae.

vii) It causes sunburn in human beings.

viii) It causes spotting of leaves in plants and trees, thus decreases productivity of the plants.

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Acid Rain:

―The rainwater which contains a large amount of poisonous acids like sulphuric acid,

sulphurous acid, nitrous acid and other pollutants is known as the Acid Rain.‖

Formation of Acid Rain

Acid rain is caused by a chemical reaction that begins when compounds like sulphur dioxide

and nitrogen oxides are released into the air. These substances can rise very high into the

atmosphere, where they mix and react with water, oxygen, and other chemicals to form more

acidic pollutants, known as acid rain. Sulphur dioxide and nitrogen oxides dissolve very

easily in water and can be carried very far by the wind. As a result, the two compounds can

travel long distances where they become part of the rain, sleet, snow, and fog that we

experience on certain days.

Causes Of Acid Rain:

Human activities are the main cause of acid rain. Over the past few decades, humans have

released so many different chemicals into the air that they have changed the mix of gases in

the atmosphere. Power plants release the majority of sulphur dioxide and much of the

nitrogen oxides when they burn fossil fuels, such as coal, to produce electricity. In addition,

the exhaust from cars, trucks, and buses releases nitrogen oxides and sulphur dioxide into the

air. These pollutants cause acid rain.

OR

The main causes of acid rain are…

Natural Sources:

• Lightning strikes (cause nitrogen molecules to be oxidized)

• Combustion of hydrogen sulphide (hydrogen sulphide is formed from the breakdown of

sulphates in organic matter in the absence of oxygen- anaerobic conditions). This reaction forms

sulphur dioxide.

Human Sources:

• Combustion engines (car, airplanes etc.)

• Burning of fossil fuels and coal

• Some mineral ores contain sulphur dioxide, and this is released when the minerals are

processed.

Effect Of Acid Rain:

i) Kills flora and fauna

ii) Damages the buildings

iii) Causes skin cancer

iv) Increases the acidity of the soil

v) Kills fish and other aquatic animals

vi) Pollutes the water

vii) Causes spotting of leaves

viii) Causes corrosion of metal, painted surfaces and even stone buildings and monuments.

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Ecosystem:

Definition:

A natural of habitat or system where living organisms and physical components of their

environment interact with one another and exchange materials so as to achieve a functional

stability is called an ecosystem.

Characteristics Of Ecosystem:

• An ecosystem is a basic unit of ecology of living organisms.

• An ecosystem may be natural like a pond, lake, stream, river, ocean or a forest.

• It may also be artificial like an Aquarian, an artificial pond or an agricultural field.

• A pond is an excellent example of a small ecosystem to demonstrate interrelationship between

abiotic and biotic component of the ecosystem.

Components Of Ecosystem:

i) Abiotic Components Of Ecosystem.

Following are the abiotic components of ecosystem.

a. Light

b. Temperature

c. Water

d. Atmosphere and wind

e. Fire

f. Soil

g. Topography

h. Gravity

i. Inorganic nutrients

ii) Biotic Factors.

Following are the biotic components of ecosystem.

a. Producers: Green Plants

b. Consumers: Animals and Man

c. Decomposers and reducers: Bacteria, fungi

Types Of Ecosystem:

There are two main types of ecosystem:

i) Terrestrial Ecosystem: it includes Forest and Desert Ecosystem

ii) Aquatic Ecosystem: it includes small pool, a pond, stream, river, lake and an oceanic

ecosystem.

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Environmental Pollution:

―Destabilization of the balance of the atmospheric composition.

OR

―It is an unstable change in the composition of the environment due to its physical, chemical and

biological changes, which is harmful for human life and other animals living on the earth.‖

Types Of Pollution:

i) Air pollution

ii) Water pollution

iii) Land pollution

iv) Noise pollution

v) Industrial pollution

vi) Commercial or domestic sector pollution

vii) Chemical pollution

viii) Radioactive pollution (contamination)

Causes of Pollution

The ultimate cause of pollution is human activity itself. Pollution is a human contribution to

nature. Science has evolved technologies and technologies have helped the human welfare. In the

process, the pollution has been a part of technology and therefore a part of human miseries.

Human activities mainly include:

• Industries for various human needs – directly and indirectly

• Agriculture for food production and industrial needs

• Health care for health of human beings and animals

• Transport for mobility of human beings

• Dwelling for settlement in city or villages

• Energy for various direct human needs and industrial needs.

Pollutants:

Pollutants are those substances which alter the natural composition of the atmosphere or destroy

it to harmful level.

Types Of Pollutants:

1. Primary Pollutants

Primary pollutants are those substances which are directly produced by a process. These are:

ix) Sulphur oxides

x) Nitrogen oxides

xi) Carbon monoxide (CO)

xii) Carbon dioxide

xiii) Volatile organic compounds (VOC), such as hydrocarbon fuel vapours and solvents

xiv) Particulate matter (PM), such as smoke and dust.

xv) Metal oxides, especially those of lead.

xvi) Chlorofluorocarbons (CFCs)

xvii) Ammonia (NH3)

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xviii) Garbage, sewage and industrial wastes.

2. Secondary Pollutants

Secondary pollutants are those pollutants which are not emitted. Rather, they form in the air when

primary pollutants react or interact.

These are:

i) Ground level ozone (O3)

ii) Nitrogen dioxide

iii) Peroxyacetyl nitrate (PAN)

Effects Of Pollution:

1) Air Pollution: Irritation of eyes, nose, mouth and throat, Increased respiratory disease, Cancer,

Reduced lung functioning, Premature death. Acid rain, Ozone,

2) Water Pollution: Waterborne diseases such as; Typhoid, Hepatitis, diarrhoea, vomiting, and

stomach aches, death of aquatic animals, May disrupt photosynthesis in aquatic plants

3) Soil Pollution: Causes cancers including leukaemia, developmental damage to the brain,

kidney damage; depression of the central nervous system, Also causes headaches, nausea, fatigue,

eye irritation and skin rash, Contamination of crops, reduce crop yields.

Water Pollution:

Definition:

―The presence of undesirable substances into fresh and natural water which cause harmful

diseases in human beings as well as aquatic life is called water pollution.‖

Types Of Water Pollution:

Following are the major types of water pollution.

i) Sea-water Pollution

ii) River water Pollution

iii) Land Water Pollution

Causes Of Water Pollution:

1) Pollution Through Domestic Activities:

Domestic activities pollute the water when following kinds of wastes are added.

i) Soap and detergents

ii) Chemicals used in the houses

iii) Waste from slaughter house

iv) Waste from hospitals

v) Waste from bakeries

vi) Human and animal faeces

vii) Waste food

2) Pollution Through Industrial Activities:

Industrial sector is a great source of pollution of water and air. Many industrial units produce

waste materials in the shape of solids, liquids and gases. The industrial wastes are.

i) Poisonous gases

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ii) Acids, bases and harmful salts

iii) Pesticides and plastics

iv) Radioactive wastes

v) Toxic wastes from fertilizer factories

vi) Wastes from chemical factories

Water Pollution In Pakistan:

In Pakistan people do not take pain to dispose the waste materials in a proper way. Instead of

dumping wastes in the drums and places meant for them they freely throw these into the water

drains.

Water pollution is very prominent and widespread as a result of urban and industrial activity.

Sewage waste from cities and industrial waste are the main factors of water pollution. Many other

kinds of wastes which pollute water are from agricultural lands which contain pesticides, waste

foods, fertilizers and animal excreta. Wastes from power plants contain radioactive materials, hot

water and minerals which also pollute the water. Soaps, detergents, human excreta, animal faeces,

wastes from slaughter houses, disease causing micro-organisms from patients and chemicals etc.

are drained into water which causes massive water pollution.

Two Important Industries Of Pakistan Causing Water Pollution:

1) One of the biggest sources of water pollution is the tanning and leather industry. The industry

uses toxic chromium metal and many other toxic substances/chemicals. These toxins are released

in natural waters. Effluent of this industry has polluted ground water and water of nearby rivers.

This industry is frequent in Kasur and Sialkot area.

2) Pesticide industry in Kala Shah Kaku near Lahore releases huge quantity of acids, pesticides

and other dangerous wastes. These wastes are getting entry into a stream flowing nearby. The

water of the stream is dangerously polluted. This water ultimately goes to the rivers.

Effects:

i) Bacteria, viruses, protozoa and worms are carried in polluted water. The diseases caused by

them are as under:

a) Bacteria: Typhoid, cholera, Dysentery, enteritis.

b) Viruses: Hepatitis, Polio, Viral enteritis.

c) Protozoa: Amoebic dysentery, diarrhoea.

d) Parasitic worms: Schistostomiasis

ii) It causes death of aquatic animals.

iii) It decreases the fertility of the soil and results in low production.

Methods To Control Water Pollution:

Different methods can be used to control water pollution.

i) The whole sewage waste should be dumped after any treatment.

ii) Sewage treatment plants should be installed in cities.

iii) The sewage waste must not be drained in river to save water from pollution.

iv) Industrial waste should be treated before reaching natural water.

v) Industries should be established away from cities and rivers.

vi) Nuclear dumping in oceans should be banned.

vii) Modern scientific methods should be used in agriculture.

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Deforestation:

It is the process of destruction of the forests.

Causes Of Deforestation:

A number of agents are responsible for removal of forests. These are fires. Droughts or animals.

The principle agent of deforestation is man himself. Humans are cutting forests to colonize the

forest areas or to prepare more agricultural lands or for getting food.

Effects Of Deforestation:

i) Deforestation has many bad effects on human life. With destruction of the forest the process of

cleaning of air and production of oxygen is badly affected.

ii) Forests are major agents of evaporation and rainfall. With deforestation rainfall is decreased.

iii) With cutting of forests, pollution is increasing as the hazardous gases are not completely

absorbed by plants.

iv) With deforestation carbon dioxide is increasing which is causing global warming.

v) With reduction in area of forest, soil erosion is taking place resulting in floods which destroy

crops and human life.

vi) Deforestation has badly damaged wild life and reduced recreation sites.

Earth:

Features Of Earth:

i) The earth is the fifth largest planet of the solar system, where life exists.

ii) Its equatorial diameter is 7,927 miles.

iii) Its polar diameter is 7900 miles.

iv) The earth has average density of 5 ½ g/cc.

v) the rotation period of the earth is 23 hours, 56 minutes and 4 seconds.

vi) the revolution period of the earth is 365 days.

vii) The total mass of the earth is 6*1021 tons.

viii) The earth is composed of shells or layers, which are, the crust, mantle and core.

ix) It is surrounded by a blanket of gases, which is known as the atmosphere, mainly composed of

Nitrogen and Oxygen.

x) The surface of the earth is rich in oxygen, silicon, iron, magnesium, sodium etc.

Structure Of The Earth:

The earth comprises of the following layers:

a) The crust

b) Moho discontinuity

c) The mantle

d) The Core

a) The Crust:

i) It is the outermost layer of the earth.

ii) It extends to about 25 miles (40kms) and comprises of rocks.

iii) The crust is divided into the oceanic and the continental crust.

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iv) Out of these the oceanic crust is 808 meter thick and consists of sedimentary mud.

v) The continental crust is divided into upper continental and lower continental crust.

b) Moho discontinuity:

i) The sharp boundary between the crust and mantle is called Moho Discontinuity.

c) The Mantle:

i) The layer of the earth lying below the crust and above the core is known as the mantle.

ii) It is almost 2900 kms (1800 miles) thick and comprises about 80% of the volume of the earth.

iii) The chemical composition of the entire mantle is fairly homogenous.

iv) However, temperature and pressure increases with depth.

v) The behaviour of the earthquake waves as they travel through the mantle further tells us that it

consists of several layers and they are:

a) Lithosphere

b) Asthenosphere

c) Mesosphere

d) The Core:

i) The innermost part of the earth is known as the core.

ii) It extends from the base of the mantle to the centre of the earth.

vi) This portion consists of melted iron and nickel that is why it is known as Nife.

vii) The density of this molten mass of the core is 345 pounds per cubic feet.

Types Of Movements Of Earth:

• There are two types of motions of the earth.

• One is around its own axis which is called Rotation. One rotation completes in 23 hours, 56

minutes and 4 seconds.

• The other motion of earth is round the sun, and is called revolution of the earth.

• One revolution completes in 365 days.

• Northern end of the earth‘s axis is called the North Pole and the Southern end is called South

Pole.

• An imaginary line drawn round the earth midway between the poles is called equator.

• The path which the earth takes round the sun is called earth‘s orbit.

Effects Of These Movements:

• Rotation of earth round its axis cause days and nights.

• That portion of earth, which is within the circle of illumination caused by the rays of sun, has its

day.

• The other side earth, which is away from sun, remains dark and therefore has its night.

Longer And Shorter Days:

• The circular areas near the North and South Pole of the Earth are called Arctic and Antarctic

circles, respectively.

• These are situated at 66 ½0 North and 66 ½0 South of the equator, respectively and form limits

of polar region.

• On June, the earth is in position A. north pole is inclined towards the sun and south pole is away

from it.

• Obviously any place in Northern Hemisphere will have longer days because it remains in light

for more than half the time of earth‘s rotation.

• Places on equator remains in light for half the time making days and nights equal in this region.

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• The southern hemisphere remains in light for less time than half the rotation of earth so the days

are shorter here.

• Positions of days and nights in the northern and southern hemisphere are reversed on 22nd

December, when the earth completes its half revolution around the sun, so days are longer in

southern hemisphere than those in the north.

Change Of Season:

• The second type of motion of earth is round the sun and is called revolution of the earth.

• This is the cause of change of seasons.

• On June 21, the earth is in position A, when the north pole is inclined towards sun while the

south pole is away from it.

• As the sun rays fall vertically and for a longer period in the northern hemisphere, it is summer

here but in the southern hemisphere it is winter.

• On December 22, when the earth completes half revolution, the conditions become reversed; it

is summer in the southern hemisphere and winter in the northern hemisphere.

Atmosphere:

The layer of the gases which surrounds the earth is known as the atmosphere.

OR

The atmosphere is a thin layer of the gases held to the earth by the gravitational attraction.

OR

Atmosphere is the huge blanket of gas that circles the entire earth.

Composition Of The Atmosphere:

The atmosphere consists of:

i) Nitrogen: 78.03%

ii) Oxygen: 20.99%

iii) Argon: 0.94%

iv) CO2: 0.03%

v) Hydrogen: 0.01%

vi) Neon: 0.0018%

vii) Helium: 0.0005%

viii) Krypton: 0.0001%

ix) Ozone: 0.000001%

Layers Of The Atmosphere:

The atmosphere of the earth is divided into following layers.

i) Troposphere

ii) Stratosphere

iii) Ionosphere

iv) Exosphere

Ionosphere is sub-divided into:

i) Mesosphere

ii) Thermosphere

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1) Troposphere:

i) Troposphere is the lowest layer of the atmosphere.

ii) It extends roughly to a height of 8 kms near the poles and 16-18 kms at the equator.

iii) It is troposphere where the people, plants, animals and insects live.

iv) It is the layer where all weather occurs that‘s why it is also referred as ―The weather Zone‖.

v) In the Troposphere temperature gradually falls with increasing altitude.

vi) There is a thin buffer zone between the troposphere and stratosphere is called tropopause.

2) Stratosphere And Ozone Layer:

i) The second layer of the atmosphere is known as the stratosphere.

ii) The stratosphere extends from the tropopause to about 30-31 mile above ground level.

iii) The important ozone layer is found in this region where heat is generated by absorption of

UV.

iv) Here the temperature either remains constant or increases with altitude.

Stratopause:

It is the upper boundary of the stratosphere which occurs beyond 52 kms. Here the temperature

remains constant with increase in height.

3) Ionosphere:

i) The third major layer of the atmosphere is the ionosphere.

ii) It lies above the stratosphere.

iii) It lies between about 30 and 90 miles above the surface of the earth.

iv) It is divided into mesosphere and thermosphere.

v) The ionosphere is bombarded by cosmic radiation and solar x-rays, which causes the gases in

the ionosphere to ionize.

vi) Brilliant displays of colored lights in the sky called Aurora Borealis in the northern

hemisphere and the Aurora Auralis in the southern hemisphere occur when streams of electrically

charged particles from the sun (solar wind) ionize the atmosphere gases.

4) Exosphere:

i) The uppermost layer of the atmosphere extending beyond Ionosphere is called exosphere.

ii) Beyond 300 miles is the very rare field exosphere which consists only of scattered atmosphere

of O, H and He.

Latitude:

Definition:

It is the distance on the surface of the earth measured in degrees north and south of the

equator.

The equator is at zero degree where the poles are at 90 degree. The latitude of the north pole

is 900 North and that of south pole is 900 South.

Characteristics OF Lines Of Latitudes:

i) All lines of latitudes are parallel to the equator as well as parallel to one another.

ii) Parallels in the north of the equator are north latitudes while those in the south of equator

are known as south latitudes.

iii) They are drawn on the globe as circles running in east to west direction.

iv) The length of the equator is the maxim um and it goes on reducing till the pole is only a

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point.

Longitude

Definition:

The distance on the earth‘s surface measures in degrees east and west of a line joining the

geographical north and south poles and passing through Greenwich in England. Greenwich is

at zero degrees longitude.

The sun rays have highest altitude simultaneously on all the places at a particular line of

longitude as a result of which these are also called as Meridians (Meridian is a Latin word

which means Mid-way). Among the latitude, equator is the longest and is taken as reference

line. But all the lines of longitude are of the same length and selecting a longitude as lines of

reference is a serious problem.

Earthquake:

Earthquakes are those movements of the earth crust which make the ground vibrated and

shake backwards and forwards or in simple words an earthquake is trembling in the earth.

The shocks waves are generated at a point within the crust called the focus, and the point on

the earth‘s surface vertically above the focus is called the epicentre of the earthquake. The

shock waves travel in all directions from the focus. On the earth‘s surface, the shaking is the

strongest near the epicentre. These waves are detected by seismograph.

Occurrence Of Earthquake:

i) Earthquakes occur when rocks subjected to great stress suddenly break, releasing the

accumulated energy, which shakes the ground. Vibrations spread out from the epicentre like

ripples in water.

ii) It may also be caused by movements of the plates, resulting from convection currents in

the hot mantle of the earth.

iii) Earthquakes are also associated with volcanic activity-eruption of magma. Collapse of

mines can also produce small earthquakes.

Volcanoes:

An opening in the earth’s crust through which molten lava, ash, and gases are ejected.

Occurrence Of Volcanoes:

i) Rocks below the Earth have a very high temperature.

ii) The great pressure upon these keeps them in a semi-solid state.

iii) If the pressure weakens, then some of rocks become liquid.

iv) This liquid is called magma.

v) The magma forces its way into cracks of the crust and may either reach the surface of the earth

where it forms lava and flow out.

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Types Of Volcanoes On The Basis Of Activity:

There are three types of volcanoes on the basis of volcanic activity, which are as under.

i) Active Volcanoes:

Volcanoes are said to be active when they frequently erupt or at least when they have erupted

within recent time.

ii) Dormant Volcanoes:

The volcanoes that have been known to erupt and show signs of possible eruption in the future

are describes as dormant volcanoes.

iii) Extinct Volcanoes:

The volcanoes that have not erupted at all in historic times but retain the features of volcanoes are

termed as extinct volcanoes.

Causes of The volcanoes Eruptions:

i) Seafloor spreading

ii) Convergence of lithospheric plates

iii) Percolation of cold water

iv) Orogenic Movements

v) High temperature in the interior of the Earth.

Rocks:

Igneous Rocks:

• The word igneous means the fires and the rocks formed by solidification of molten rock

material known as magma are known as igneous rocks.

• The first minerals to crystalize out of the melt are high-temperature minerals-the olivines and

pyroxenes, which are silicates of magnesium and iron.

• They tend to be denser than magma and so they sink, leaving the remaining fluid deficient in

magnesium and iron.

• The next group of minerals to solidify are the feldspars (silicates minerals of potassium, sodium,

calcium and aluminium); the magma thus loses its metallic constituents first.

• Finally, any remaining silica crystalizes out as quartz.

• The entire solidification process therefore results in dense iron-and magnesium-rich rocks and

less dense silica rich rocks from the same original fluid.

• In this way, different types of rocks can be seen in the same rock mass.

• The most important igneous rocks are: a) Granite rocks b) Gabboro rocks c) Basalt rocks

Sedimentary Rocks:

• Sedimentary rocks are formed from the deposition and compaction or lithification of rocks and

mineral grains derived from other rocks.

• These grains broke away from existing rocks by the action of water, wind and ice.

• Many sedimentary rocks begin their existence as loose deposits of sand or gravel at the bottom

of a sea or lake, on beach, or in a desert.

• Later the sediment is lithified i.e. compressed into a rock.

• Following are the major classes of sedimentary rocks:

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i) Calcareous sedimentary rocks

ii) Carbonaceous sedimentary rocks

iii) Siliceous sedimentary rocks

iv) Ferruginous sedimentary rocks

v) Arenaceous sedimentary rocks

vi) Argillaceous sedimentary rocks

vii) Rudaceous sedimentary rocks

Metamorphic Rocks:

• The word metamorphic has been derived from two Greek words Meta means change and

Morpha means shape.

• Thus metamorphic rocks include those rocks that have been changed either in form or

composition without disintegration.

• Metamorphic rocks are formed from igneous as well as sedimentary rocks but are different from

them.

Example:

i) Sandstone, made of quartz grains and silica cement, becomes quartzite, a very hard metaphoric

rock that resist weathering.

ii) Limestone is converted into much denser and harder marble.

iii) Mica, an igneous rock, is converted into schist after metamorphosis.

iv) Sedimentary rock slate is converted into a slightly higher grade metamorphic rock phyllite.

Branches Of Biology:

i) Zoology: Zoology is that branch of biology which deals with the study of animals.

ii) Botany: Botany is that branch of biology which deals with the study of plants.

iii) Microbiology: It is the branch of biology which deals with the study of microorganisms such

as viruses, bacteria etc.

iv) Morphology: It deals with the shape and structure of living organisms.

v) Histology: It is the microscopic study of tissues of plants and animals.

vi) Cytology: It deals with the structure of cell and organelles present inside the cell.

vii) Physiology: It deals with the study of functions of different parts of plants and animals.

viii) Ecology: It is the science of ecosystem and explains the relationship between organisms and

their environment.

ix) Taxonomy: It deals with the naming and classification of organisms.

x) Genetics: It deals with the study of heredity and variations.

xi) Biotechnology: It deals with the application of biological processes.

xii) Haematology: Study of blood and its constituent cells.

xiii) Geology: Study of features and properties of earth and its constituents rocks

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Characteristics Of Living Organisms:

Following are the main characteristics of living beings which are not present in non-living

organisms.

i) Metabolism

ii) Growth

iii) Irritability

iv) Reproduction

v) Movement

vi) Nutrition

vii) Respiration

viii) Excretion

Virus:

• Viruses are the micro-organisms which are strict or obligate parasites of animals or plant

cells.

• Many of the viruses are also parasites on bacteria.

• A large number of viruses cause diseases in plants and animals.

Characteristics Of Virus:

• A virus consists of two components, a protein coat and a core of nucleic acid which is either

DNA or RNA.

• DNA viruses are called adenoviruses and RNA viruses are called retroviruses.

• The shape of a virus is due to its protein coat.

• Viruses are of many shapes i.e. rods, spherical, hexagonal or icosahedral.

• Sometimes their shape is complicated.

• Virus replicate inside a living cell and many viruses are synthesized along with their protein

coats and nucleic acid.

• The nucleic acid contains instructions for the shape of the virus.

Diseases Caused By viruses:

i) Polio

ii) AIDS

iii) Smallpox

iv) Measles

v) Hepatitis

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Bacteria:

Characteristics Of Bacteria:

• Bacteria are unicellular prokaryotic organisms which generally divide by transverse binary

fission.

• They possess rigid cell walls and act as pathogens

• Nucleus is not well organised

• No definite chloroplast, chlorophyll is dissolved in chromoplasm.

• There are three forms of bacteria which are:

i) Round called Cocci

ii) Rod like called Bacilli

iii) Spiral called Spirrila

Classification Of Bactria According To Mode Of Nutrition:

According to mode of nutrition, there are three types of Bactria:

a) Parasitic:

• Devoid of chlorophyll

• Are heterotrophic and get food from living animals and plants

b) Saprophytic

• Lack chlorophyll hence cannot prepare their own food.

• Get food from dead organic remains

c) Autotrophic

• Contain chlorophyll

• Can synthesis food by photosynthesis

• Few get their food by chemosynthesis

Reproduction In Bacteria

i) Vegetative: By Binary Fission

ii) Asexual: By Formation of Endospores

iii) Sexual: By Conjugation

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Cell Division:

The process in which the cells divide and replicate. This process is the basis for growth and

replication. There are two main types of cell division, which are as under:

1) Mitosis

2) Meiosis

Mitosis:

A type of cell division in which a cell divides into two identical daughter cells each having

same number of chromosomes as that of parent cell.

Stages Of Mitosis:

There are four stages of mitosis, which are as under:

i) Prophase

ii) Metaphase

iii) Anaphase

iv) Telophase

i) Prophase:

– Prophase is the first phase of mitosis.

– Chromatin material condenses and becomes visible

– The nucleolus of the cell disappears

– The nuclear membrane also disappears

– Centrioles begin to move opposite ends of the cell

ii) Metaphase:

– Metaphase is the second stage of mitosis.

– Chromosomes line up in the centre of the cell, separate and become a pair of identical

chromosomes.

– The chromatids become uncoiled and apart from each other.

iii) Anaphase:

– It is the third phase of mitosis.

– During this phase each set of chromosomes move towards the opposite end of the cell.

iv) Telophase:

– The fourth phase of mitosis is known as Telophase.

– During this phase spindle fibres disappear.

– Nuclear membrane appears

– Cell divides into two daughter cells

– Nucleolus re-appear

– The chromosomes disperse and are no longer visible.

Significance Of Mitosis:

1. Growth: The number of cells within an organism increases by mitosis and this is the basis

of growth in multicellular organisms.

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2. Cell Replacement: Cells are constantly sloughed off, dying and being replaced by new

ones in the skin and digestive tract. When damaged tissues are repaired, the new cells must be

exact copies of the cells being replaced so as to retain normal function of cells.

3. Regeneration: Some animals can regenerate parts of the body, and productions of new cells

are achieved by mitosis.

4. Vegetative Reproduction: Some plants produce offspring which are genetically similar to

themselves. These offspring are called clones.

Meiosis:

A type of cell division in a cell divides into four daughter cells with having half number of

chromosomes as compared to parent cell.

Characteristics Of Meiosis:

• Takes place in sexual reproduction at the time of formation of male and female gametes

• In animals it takes place during the formation of sperms and ova while in plants during spore

formation

• Diploid cells reduce to haploid cells

• Consists of two consecutive divisions

• First division is reductional or meiotic and the second is simple mitotic division.

Stages Of Meiotic Division:

i) Prophase I

ii) Metaphase I

iii) Anaphase I

iv) Telophase I

v) Prophase II

vi) Metaphase II

vii) Anaphase II

viii) Telophase II

Prophase I:

Prophase I consists of 5 sub stages, these are:

a. Leptotene

– Nucleus increases in size

– Chromosomes become long and uncoiled threads

– They become more visible

b. Zygotene

– Homologue (similar) chromosomes attract each other and form pairs.

– This process is called synapses

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c. Pachytene

– Chromosomes become condensed due to widening of coils

– They form chiasmata i.e. cross each other in double nature or bivalents.

d. Diplotene

– Homologous chromosomes go apart from each other except at chiasmata

– Chromosomes become more short and thicker

e. Diakinesis

– The bivalents become more apart.

– Chromosomes become deeply stained

– Nucleolus and nuclear membrane disappear and spindles become distinct

Metaphase I:

– Chromosomes now rearrange themselves in an equatorial line

– Spindles attach to the centrosome of the chromosomes

Anaphase I:

– Spindles start to contract

– Split the tetrahedral chromosomes into two chromatids and drag them to opposite poles

– Here the reduction takes place.

Telophase I:

– Spitted chromosomes reach to opposite poles

– Nucleolus and nuclear membrane reappear

– At the end of Telophase I, prophase II starts.

Prophase II:

– Chromatin network breaks into bivalent chromosomes

– Nuclear membrane and nucleolus disappear and spindles start to reappear

Metaphase II:

– Bivalent chromosomes rearrange themselves at equator

– Spindles attach to the centrosomes of each chromosome

Anaphase II:

– Spindles contract and split the chromosomes longitudinally into two chromatids

– Each chromatid travel to opposite pole

Telophase II:

– Each chromatid reach to the opposite pole

– Spindles disappear and nuclear membrane and nucleoli reappear

– As a result 4 nuclei are formed

Significance Of Meiosis:

– To allow trait inheritance in offspring

– To maintain diploid number in each generation

– To ensure the production of haploid gametes in sexual reproduction

– To produce genetic variations among offspring

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Classification Of Plants:

Plants are those organisms which contain chlorophyll and synthesize their own food through

photosynthesis. Plants are divided into:

1) Flowering Plants OR Phanerogams

2) Non-Flowering Plants OR Cryptogams

Flowering Plants:

Flowering plants are those plants which contain seed. These are known as Phanerogams.

They are further subdivided into:

i) Gymnosperms

ii) Angiosperms

Gymnosperms:

Gymnosperms are those flowering plants which contain naked and unprotected seeds.

Examples: Pine, Fir, Cedar, Spruce and Cypress etc.

Angiosperms:

Angiosperms are those flowering plants whose seeds are protected by a fruit or seed pod.

Examples: Grass, Crops, Vegetables, Fruits and weeds.

Non-Flowering Plants:

Non-Flowering plants are also known as cryptogams. These are the plants which do not have

seed or in other words they are seedless. Following are the main characteristics of these

plants:

– They reproduce by spores

– They have long life

– They have no long fibres

– They cannot grow to greater size

– They generally have simple structure, except ferns.

Examples: Moses, Ferns, Algae.

Flower & Its Parts:

The flower is the reproductive part of the plant. It is mainly concerned with formation of

seeds. It is regarded as the modified shoot for the purpose of reproduction.

Parts Of Flower:

A typical flower consists of a short axis known as the thalamus, on which floral leaves are

inserted in four distinct whorls, which are as under:

i) Calyx

ii) Corolla

iii) Androecium

iv) Gynaecium

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Calyx:

Calyx is the outermost whorl of floral leaves called sepals. The sepals can be defined as the

green and leaf like structures which are mainly concerned with the protective function.

Corolla:

Corolla is the second whorl of floral leaves called petals. The petals are beautifully coloured

which are responsible for the attraction to the insects towards them.

Androecium:

The third whorl of the leaves consists of stamens. It is considered as the male part of the

flower.

Gynaecium:

Gynaecium is the inner most whorl of the floral leaves called carpels. It is considered as the

female part of the flower.

Parts Of Plants:

i) Ginger: Modified Stem (rhizome) and it is also a root.

ii) Cinnamon: Bark of stem

iii) Radish: Root

iv) Potato: Stem (tuber)

v) Peanut: Seed

vi) Saffron: Stigma/flower

vii) Almond: Fruit

viii) Chillies: Fruit

ix) Spinach: Leaves

x) Tomato: Fruit

xi) Turnip: Root

xii) Carrot: Root

xiii) Cucumber: Fruit

Photosynthesis:

Definition:

Photosynthesis is a process in which plants manufacture their food (simple carbohydrates) in

the presence of chlorophyll and sunlight by the combination of carbon dioxide and water.

Raw Material For Photosynthesis:

i) Carbon dioxide: Taken from air

ii) Water: Absorbed by roots from soil

iii) Sunlight: From Sun

iv) Chlorophyll: green pigment present in leaves

By-Products Of Photosynthesis:

i) Carbohydrates (simple sugar): used by plants as a food material and excess of it is

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converted into starch

ii) Oxygen: Released into air

Importance Of Photosynthesis:

i) Major process of food production in plants

ii) Utilization of CO2 of the atmosphere and liberation of oxygen

iii) Important in reducing CO2 of the atmosphere which is dangerous for the human beings as

well as animal health.

Pollination:

• It is the process by which seeds are produced.

Definition:

Pollination is the phenomenon of transfer of pollen from male reproductive organ (anther) to

female reproductive organ (stigma) in flowering plants through biological or physical agency.

Types Of pollination:

There are two types of Pollination

i) Self-Pollination:

In this type of pollination pollens are transferred to the stigma in the same flower. Some

plants are by nature self-pollinated as wheat and grasses.

ii) Cross Pollination:

In this type the pollen grains are transferred from the anther of one flower to the stigma of

another flower. The cross pollination is considered and advantageous to the plant as the seeds

produced by cross-pollination are usually greater in number and the plant germinated from

them are superior in vigour, height and weight.

Vehicles For Pollination:

Vehicles for pollination are animals, water, wind and insects. Therefore cross pollination may

be:

a) Entomophily-by insects

b) Anemophily-by wind

c) Hydrophily-by water

d) Zoophily-by animals

Importance Of Pollination:

• Vital process for reproduction in plants

• Reproduction is carried out by reproductory organs of plants due to pollination

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Fertilization:

The fusion of male and female gametes is called fertilization.

Types Of Fertilization:

Following are the major types of fertilization:

i) External Fertilization

ii) Internal Fertilization

iii) Self-Fertilization

iv) Cross-Fertilization

External Fertilization:

• This type of fertilization is generally observed I simple aquatic animals.

• In such animals both ova and sperms are released into the water where fertilization occurs.

• In terms of evolution external fertilization is of primitive type and is not better biologically as

compared to internal fertilization.

Internal Fertilization:

• In the internal fertilization the females keep ova inside their bodies and males deposit sperms

within the tube of reproductive tacts of females.

• For all land animals internal fertilization is almost must because sperms are quickly killed by

dehydration.

• In terms of evolution internal fertilization is highly evolved and much better biologically as

compared to external fertilization.

Self-Fertilization:

• Self-fertilization occurs within the same animal.

• It is that fertilization in which sperms are used by the ovaries of same animal e.g. Tapeworm

Cross-fertilization:

• Cross-fertilization is the process in which sperms of one animal are transferred into the body of

another animal e.g. Earthworm.

Genetic Engineering:

The deliberate modification of the characteristics of an organism by manipulating its genetic

material.

OR

Scientific alteration of the structure of genetic material in a living organism. It involves the

production and use of recombinant DNA and has been employed to create bacteria that

synthesize insulin and other human proteins.

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Significance Of Genetic Engineering:

i) To Cure the genetic disorders

Heredity diseases can possibly be treated by this technique by transplanting normal genes in

the place of abnormal or diseased genes.

ii) To Prepare Better Crops

Crops with desired characteristics could possibly be produced by introducing desired genes.

iii) To Get Better Breeds Of Animals

Like plants better breeds of animals can also be produced by the introduction of recombinant

DNA.

iv) Interferon

Interferons are effectively used in the treatment of Hepatitis of A & B.

v) Insulin

Human insulin is being produced by genetic engineering to treat diabetes

vi) Vaccines

Genetic engineering has also helped in the production of vaccines which are used for

controlling and treating viral diseases.

Biotechnology:

The exploitation of biological processes for industrial and other purposes, esp. the genetic

manipulation of microorganisms for the production of antibiotics, hormones, etc.

OR

Biotechnology is the use of living organisms (especially microorganisms) in industrial,

agricultural, medical and other technological applications.

Importance Of Biotechnology:

i) To increases production

ii) To introduce improved quality of seeds and plants

iii) To introduce plants resistant to disease and insect pests

iv) To introduce verities suited to particular climates and soils.

v) To introduce verities resistant to lodging

vi) To improve nutritional value of crops

vii) To save rare varieties of plants by rapid clonal propagation for breeders to use in future.

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Teeth:

The humans have two sets of teeth one replaced by the second. The primary set or milk or

deciduous teeth are 20 in number while there are 32 permanent teeth in adults.

1. In children there are 20 deciduous or milk teeth. These are

Incisor: 2 pair × 2= 8

Canine: 1 pair × 2= 4

Premolars: 2 pair× 2=8

2. In adults there are 32 permanent teeth. In each jaw on each side there are:

Incisors: 2 pair × 2=8

Canines: 1 pair × 2=4

Premolars: 2 pair × 2=8

Molars: 3 pair × 2= 12

Incisors:

The central front teeth are called incisors. There are four in upper jaw and four in lower jaw.

Canines:

The pointed, dark colored teeth on either side of the incisors are canines. 2 in upper jaw and 2 in

lower jaw.

Premolars:

These are bi-cusped teeth after the canines. There are 8 premolars. 4 in the upper jaw and 4 in the

lower.

Molars:

There are 12 molars, 6 in the upper jaw and 6 in the lower jaw.

Structure Of Teeth:

Each tooth consists of a crown which is the visible part and the root, which anchors it in sockets

in the jaw. A tooth consists mainly of dentine. The crown is coated with even harder enamel,

while the root is covered with cementurn to help another it in the jaw. Inside each tooth, there is a

cavity full of pulp, carrying nerves and the tooth‘s blood and eats through the dentine to the pulp

when the decay reaches the pulp, pain and inflammation follows and tooth may die.

A nerve, an artery, a vein and lymph duct enters the pulp cavity through the root canal. The

nerves give sensation of hot and cold.

Antibody:

Antibody is a protein produced by white blood cells that help to destroy bacteria. Antibodies

react with the antigens and inactivate or destroy them. A large number of antibodies are

produced in blood which are targeted against various types of antigens. Antigens are foreign

molecules, cells, bacteria, viruses or fungi which enter the body usually a disease causing

microorganisms. Antibodies are the integral part of the defence mechanism of human body.

They are also involved in immunity against disease.

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Hemophilia:

• It is a disease in which the peron have prolonged blood clotting time resulting in excessive

bleeding fron injury.

• It is due to the deficiency of vitamin K.

• It is a semilethal disease controlled by recessive gene.

• It is less common in women than in men.

Important Facts About Human Physiology:

The largest gland of the body: Liver

The largest organ of the body: Skin

The longest bone of the body: Femur

The total number of bones in the body: 206

The hardest bone of the body: Tooth

The smallest bone of the body: Stapes

Total number of muscles in the body: 600

The filter of the body: Kidney

The pump of the Body: Heart

Total number of bones in vertebral column: 33

The normal body temperature: 98.4 F (37 C)

The normal respiratory rate of the Body: 16-18 per min

The total volume of blood in body: 4-5 litres

Total number of bones in face: 14

Vascular connection between foetus and uterus: Placenta

Brain:

Human brain is contained in skull. It has three major parts.

i) The Cereberum ot bigger brain

ii) The Cerebellum or Smaller brain

iii) Medulla Oblongata or hind brain

The cereberum constitutes the major volume of brain. It consists of two large masses of

nervous material known as cereberal hemispheres. Human consciousness, thought, emotions,

sight, will, hearing, sensation of pain, memory and speech are centere in the creberum. Some

parts of it also control motor nerves, operating the arms and legs.

The cerebellum or the smaller brain is related with the coordination of action of nerves and

muscles. In this way movements of body are manged. Medulla or hind brain contains the

centres for reflex actions in addition to automatic movements such as breathing and walking.

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Reflex Action:

– Reflex actions are the responsed to environmental changes both internal and external and are

immediate or automatic and are without intervention of will.

– These reflexes amy be simple or conditioned e.g. watering of mouth on seeing or smelling of

food.

– Simple reflexes are inborn, inherited or unlearnt responses to stimuli.

– The structural and functional basis of simple reflex is called reflex arc.

– Impulses are carried from receprtors to sensory neurons to CNS from where they are passed on

via motor neurons to the effectors for necessary response.

Thermoplastics:

Substances (esp. synthetic resins) that become plastic on heating and harden on cooling and

are able to repeat these processes

OR

A type of plastic that can be softened by heat, hardened by cooling, and then softened by heat

over and over again.

Properties of Thermoplastics:

Thermoplastics have wide ranging properties.

– They can be very much like rubber, or as strong as aluminium.

– are light in weight,

– Can withstand temperature extremes of up to 600 F, while others retain their properties at –

100 F. Some

– Thermoplastic materials have no known solvents at room temperature.

– Most thermoplastic materials are excellent insulators, both electrical and thermal.

– Are recyclable materials that are used frequently today to create objects such as foam cups,

polyethylene squeeze bottles, acrylic lenses and safety helmets.

– In general the combination of light weight, high strength, and low processing costs make

thermoplastics well suited to many applications.

Uses:

– They are useful for a variety of applications, including consumer goods, machine parts,

medical equipment and packaging and storage materials.

Examples:

• PVC/Vinyl

• Polystyrene

• Polyethylene

• Cellulose Acetate

• PTFE/Teflon

• Nylon/Polyamide

• Polyester

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Synthetic Polymers:

Polymers are composed of very large molecules (macromolecules) formed by linking together

many smaller, more simple units called monomers. There can be as few as five or as many as

several thousand monomers units in a polymer. There are a large number of synthetic polymers

prepared and in use. Some of these are polyamides(nylon), polyethylene, propylene,

polyvinylchloride, synthetic rubber, cellulose acetate, cellulose nitrate and silicones.

Heredity:

Terminology Of Genetics:

Gene:

The basic unit of hereditary material which is responsible for development of a trait.

Alleles:

Alternatives forms of genes are called alleles, e.g. tall versus dwarf.

Dominant:

The dominant alleles are those traits which show complete expression even in heterozygous state.

Dominant alleles dominate the recessive alleles in heterozygous state.

Recessive:

Recessive alleles or traits are those which fail to express themselves in heterozygous state. For

example r and y are recessive alleles for wrinkle and green seeds.

Homozygous:

Homozygous is a condition in which an individual possess similar alleles for a particular trait. For

example TT for tallness and tt for dwarfness.

Heterozygous:

Heterozygous is a condition in which an individual possess dissimilar alleles for a particular trait.

For example Tt for tallness.

Genotype:

Genetic make of an organism is called genotype.

Phenotype:

External appearance or expression of genotype is called phenotype. For example, roundness,

wrinkleness of seeds and tall or dwarf plants represent different phenotype.

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Gene:

Definition:

The fundamental unit of heredity, formed as a sequence of bases in DNA.

Characteristics Of Genes:

• Each gene has a definite position at the chromosome and may occur as alleles.

• The name gene was introduced by Johannsen in 1909 and the structure of DNA was elaborated

by Watson and Crick in 1953.

• Genes determine all the structural and functional characters of an individual, like eye colour,

skin colour, height, weight, blood group, hair, intelligence, temperament and all others.

• The characters from one generation to other are taken by genes.

• They sometimes change through the process of mutation. This gives variety in characters.

• The accurate structure of the proteins and enzymes in the body is determined by genes.

Chromosomes:

A chromosome is a rod-like portion of the chromatin of a cell nucleus, performing an important

part in meiotic cell division, and in the transmission of heredity characteristics. Normally they are

constant in number for any species; there are 22 pairs of chromosomes and two sex chromosomes

in the human.

Types Of Chromosomes: in higher animals and plants, there are two fundamental types of

chromosomes, which are classified on the basis of sex determination these are:

i) Autosomes

ii) Sex Chromosomes:

Autosomes:

These are paired somatic chromosomes that play no part in sex determination of organisms.

These chromosomes are similar in males and females.

Sex Chromosomes:

The chromosomes that determine sex in organisms are called sex chromosomes. There are two

types of sex chromosomes.

a) X- chromosome

b) Y- Chromosome

Animals:

Types Of Animals:

i) Invertebrates: Animals having no backbone or vertebral column.

ii) Vertebrates: Animals with backbone or vertebral column.

Classification Of Invertebrates:

The invertebrates are classified into following categories:

i) Phylum Protozoa

ii) Phylum Porifera

iii) Phylum Coelentrata

iv) Phylum Platyhelminthes

v) Phylum Nematode

vi) Phylum Annelida

vii) Phylum Mollusca

viii) Phylum Arthropoda

ix) Phylum Echinodermata

Following are the most common examples of invertebrate animals with their relative phyla:

– Euglena: Phylum Protozoa

– Paramecium: Phylum Protozoa

– Amoeba: Phylum Protozoa

– Sponges: Phylum Porifera

– Hydra: Phylum Coelentrata

– Jelly fish: Phylum Coelentrata

– Tapeworm: Phylum Platyhelminthes

– Ascaris: Phylum Nematode

– Hookworm: Phylum Nematode

– Filaria: Phylum Nematode

– Snails: Phylum Mollusca

– Squids: Phylum Mollusca

– Cockroach: Phylum Arthropoda

– Honey bee: Phylum Arthropoda

– Mosquito: Phylum Arthropoda

– Butter fly: Phylum Arthropoda

Classification Of Vertebrates:

Vertebrates have been divided into following five major classes:

i) Fishes

ii) Amphibians

iii) Reptilian

iv) Birds

v) Mammals

Some Animals & Their Location

i) Blue whale: Found in all oceans

ii) Panda: China

iii) Dolphin: In seas

iv) Porpoises:

v) Kangaroo: Australia

vi) Snow Leopard: Central Asia

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vii) Yak: Central Asia

viii) Llama: South America

ix) Ibex: Wild mountain goat

x) Cobra: South Asia

xi) Alligator: N.America

xii) Tortoise: Water

xiii) Rattle Snake: America

xiv) Lizards:

xv) Crocodiles:

xvi) Ostrich: Deserts Of Africa

xvii) Penguin: Antarctic Region

xviii) Kiwi: New Zealand

xix) Rhea: South America

xx) Emu: Australia

xxi) Shark: Found in all oceans

xxii) Trout: Fresh water fish

xxiii) Cod:

Scavenger:

Scavengers are the animals that ‗Clean up‘ after the other animals by consuming their leavings and

sometimes prey on sick or dying animals or consume dead bodies. Scavengers are also called detritus

feeders. Vultures, coyotes, jackals, hyenas and wild dogs are scavengers which eat the left over prey or

dead bodies of hunted animals.

List of International Organisations – Headquarters in Geneva


Geneva is called the city of conferences. I have tried to consolidate the list of international organisations who have their headquarters based in Geneva. Courtesy: Wikipedia

Following is the list: 

Dictionary – Vocabulary


 

abase v. To lower in position, estimation, or the like; degrade. ← Many vocabulary words, such as degrade, are repeated in definitions for double learning
abbess n. The lady superior of a nunnery. 
abbey n. The group of buildings which collectively form the dwelling-place of a society of monks or nuns.   Free SAT prep math notes below vocabulary ↓ 
abbot n. The superior of a community of monks. 
abdicate v. To give up (royal power or the like). 
abdomen n. In mammals, the visceral cavity between the diaphragm and the pelvic floor; the belly. 
abdominal n. Of, pertaining to, or situated on the abdomen. 
abduction n. A carrying away of a person against his will, or illegally. 
abed adv. In bed; on a bed. 
aberration n. Deviation from a right, customary, or prescribed course. 
abet v. To aid, promote, or encourage the commission of (an offense). 
abeyance n. A state of suspension or temporary inaction. 
abhorrence n. The act of detesting extremely. 
abhorrent adj. Very repugnant; hateful. 
abidance n. An abiding. 
abject adj. Sunk to a low condition. 
abjure v. To recant, renounce, repudiate under oath. 
able-bodied adj. Competent for physical service. 
ablution n. A washing or cleansing, especially of the body. 
abnegate v. To renounce (a right or privilege). 
abnormal adj. Not conformed to the ordinary rule or standard. 
abominable adj. Very hateful. 
abominate v. To hate violently. 
abomination n. A very detestable act or practice. 
aboriginal adj. Primitive; unsophisticated. 
aborigines n. The original of earliest known inhabitants of a country. 
aboveboard adv. & adj. Without concealment, fraud, or trickery. 
abrade v. To wear away the surface or some part of by friction. 
abrasion n. That which is rubbed off. 
abridge v. To make shorter in words, keeping the essential features, leaning out minor particles. 
abridgment n. A condensed form as of a book or play. 
abrogate v. To abolish, repeal. 
abrupt adj. Beginning, ending, or changing suddenly or with a break. 
abscess n. A Collection of pus in a cavity formed within some tissue of the body. 
abscission n. The act of cutting off, as in a surgical operation. 
abscond v. To depart suddenly and secretly, as for the purpose of escaping arrest. 
absence n. The fact of not being present or available. 
absent-minded adj. Lacking in attention to immediate surroundings or business. 
absolution n. Forgiveness, or passing over of offenses. 
absolve v. To free from sin or its penalties. 
absorb v. To drink in or suck up, as a sponge absorbs water. 
absorption n. The act or process of absorbing. 
abstain v. To keep oneself back (from doing or using something). 
abstemious adj. Characterized by self denial or abstinence, as in the use of drink, food. 
abstinence n. Self denial. 
abstruse adj. Dealing with matters difficult to be understood. 
absurd adj. Inconsistent with reason or common sense. 
abundant adj. Plentiful. 
abusive adj. Employing harsh words or ill treatment. 
abut v. To touch at the end or boundary line. 
abyss n. Bottomless gulf. 
academic adj. Of or pertaining to an academy, college, or university. 
academician n. A member of an academy of literature, art, or science. 
academy n. Any institution where the higher branches of learning are taught. 
accede v. To agree. 
accelerate v. To move faster. 
accept v. To take when offered. 
access n. A way of approach or entrance; passage. 
accessible adj. Approachable. 
accession n. Induction or elevation, as to dignity, office, or government. 
accessory n. A person or thing that aids the principal agent. 
acclaim v. To utter with a shout. 
accommodate v. To furnish something as a kindness or favor. 
accompaniment n. A subordinate part or parts, enriching or supporting the leading part. 
accompanist n. One who or that which accompanies. 
accompany v. To go with, or be associated with, as a companion. 
accomplice n. An associate in wrong-doing. 
accomplish v. To bring to pass.
accordion n. A portable free-reed musical instrument. 
accost v. To speak to. 
account n. A record or statement of receipts and expenditures, or of business transactions. 
accouter v. To dress. 
accredit v. To give credit or authority to. 
accumulate v. To become greater in quantity or number. 
accuracy n. Exactness. 
accurate adj. Conforming exactly to truth or to a standard. 
accursed adj. Doomed to evil, misery, or misfortune. 
accusation n. A charge of crime, misdemeanor, or error. 
accusatory adj. Of, pertaining to, or involving an accusation. 
accuse v. To charge with wrong doing, misconduct, or error. 
accustom v. To make familiar by use. 
acerbity n. Sourness, with bitterness and astringency. 
acetate n. A salt of acetic acid. 
acetic adj. Of, pertaining to, or of the nature of vinegar. 
ache v. To be in pain or distress. 
Achillean adj. Invulnerable. 
achromatic adj. Colorless, 
acid n. A sour substance. 
acidify v. To change into acid. 
acknowledge v. To recognize; to admit the genuineness or validity of. 
acknowledgment n. Recognition. 
acme n. The highest point, or summit. 
acoustic adj. Pertaining to the act or sense of hearing. 
acquaint v. To make familiar or conversant. 
acquiesce v. To comply; submit. 
acquiescence n. Passive consent. 
acquire v. To get as one’s own. 
acquisition n. Anything gained, or made one’s own, usually by effort or labor. 
acquit v. To free or clear, as from accusation. 
acquittal n. A discharge from accusation by judicial action. 
acquittance n. Release or discharge from indebtedness, obligation, or responsibility. 
acreage n. Quantity or extent of land, especially of cultivated land. 
acrid adj. Harshly pungent or bitter. 
acrimonious adj. Full of bitterness. 
acrimony n. Sharpness or bitterness of speech or temper. 
actionable adj. Affording cause for instituting an action, as trespass, slanderous words. 
actuality n. Any reality. 
actuary n. An officer, as of an insurance company, who calculates and states the risks and premiums. 
actuate v. To move or incite to action. 
acumen n. Quickness of intellectual insight, or discernment; keenness of discrimination. 
acute adj. Having fine and penetrating discernment. 
adamant n. Any substance of exceeding hardness or impenetrability. 
addendum n. Something added, or to be added. 
addle v. To make inefficient or worthless; muddle. 
adduce v. To bring forward or name for consideration. 
adhere v. To stick fast or together. 
adherence n. Attachment. 
adherent adj. Clinging or sticking fast. 
adhesion n. The state of being attached or joined. 
adieu inter. Good-by; farewell. 
adjacency n. The state of being adjacent. 
adjacent n. That which is near or bordering upon. 
adjudge v. To award or bestow by formal decision. 
adjunct n. Something joined to or connected with another thing, but holding a subordinate place. 
adjuration n. A vehement appeal. 
adjutant adj. Auxiliary. 
administrator n. One who manages affairs of any kind. 
admissible adj. Having the right or privilege of entry. 
admittance n. Entrance, or the right or permission to enter. 
admonish v. To warn of a fault. 
admonition n. Gentle reproof. 
ado n. unnecessary activity or ceremony. 
adoration n. Profound devotion. 
adroit adj. Having skill in the use of the bodily or mental powers. 
adulterant n. An adulterating substance. 
adulterate v. To make impure by the admixture of other or baser ingredients. 
adumbrate v. To represent beforehand in outline or by emblem. 
advent n. The coming or arrival, as of any important change, event, state, or personage. 
adverse adj. Opposing or opposed. 
adversity n. Misfortune. 
advert v. To refer incidentally. 
advertiser n. One who advertises, especially in newspapers. 
advisory adj. Not mandatory. 
advocacy n. The act of pleading a cause. 
advocate n. One who pleads the cause of another, as in a legal or ecclesiastical court. 
aerial adj. Of, pertaining to, or like the air. 
aeronaut n. One who navigates the air, a balloonist. 
aeronautics n. the art or practice of flying aircraft 
aerostat n. A balloon or other apparatus floating in or sustained by the air. 
aerostatics n. The branch of pneumatics that treats of the equilibrium, pressure, and mechanical properties. 
affable adj. Easy to approach. 
affect v. To act upon 
affectation n. A studied or ostentatious pretense or attempt. 
affiliate n. Some auxiliary person or thing. 
affirmative adj. Answering yes; to a question at issue. 
affix v. To fasten. 
affluence n. A profuse or abundant supply of riches. 
affront n. An open insult or indignity. 
afire adv. & adj. On fire, literally or figuratively. 
afoot adv. In progress. 
aforesaid adj. Said in a preceding part or before. 
afresh adv. Once more, after rest or interval. 
afterthought n. A thought that comes later than its appropriate or expected time. 
agglomerate v. To pile or heap together. 
aggrandize v. To cause to appear greatly. 
aggravate v. To make heavier, worse, or more burdensome. 
aggravation n. The fact of being made heavier or more heinous, as a crime , offense, misfortune, etc. 
aggregate n. The entire number, sum, mass, or quantity of something. 
aggress v. To make the first attack. 
aggression n. An unprovoked attack. 
aggrieve v. To give grief or sorrow to. 
aghast adj. Struck with terror and amazement. 
agile adj. Able to move or act quickly, physically, or mentally. 
agitate v. To move or excite (the feelings or thoughts). 
agrarian adj. Pertaining to land, especially agricultural land. 
aide-de-camp n. An officer who receives and transmits the orders of the general. 
ailment n. Slight sickness. 
airy adj. Delicate, ethereal. 
akin adj. Of similar nature or qualities. 
alabaster n. A white or delicately tinted fine-grained gypsum. 
alacrity n. Cheerful willingness. 
albeit conj. Even though. 
albino n. A person with milky white skin and hair, and eyes with bright red pupil and usually pink iris. 
album n. A book whose leaves are so made to form paper frames for holding photographs or the like. 
alchemy n. Chemistry of the middle ages, characterized by the pursuit of changing base metals to gold. 
alcohol n. A volatile, inflammable, colorless liquid of a penetrating odor and burning taste. 
alcoholism n. A condition resulting from the inordinate or persistent use of alcoholic beverages. 
alcove n. A covered recess connected with or at the side of a larger room. 
alder n. Any shrub or small tree of the genus Alumnus, of the oak family. 
alderman n. A member of a municipal legislative body, who usually exercises also certain judicial functions.
aldermanship n. The dignity, condition, office, or term of office of an alderman. 
alias n. An assumed name. 
alien n. One who owes allegiance to a foreign government. 
alienable adj. Capable of being aliened or alienated, as lands. 
alienate v. To cause to turn away. 
alienation n. Estrangement. 
aliment n. That which nourishes. 
alkali n. Anything that will neutralize an acid, as lime, magnesia, etc. 
allay v. To calm the violence or reduce the intensity of; mitigate. 
allege v. To assert to be true, especially in a formal manner, as in court. 
allegory n. The setting forth of a subject under the guise of another subject of aptly suggestive likeness. 
alleviate v. To make less burdensome or less hard to bear. 
alley n. A narrow street, garden path, walk, or the like. 
alliance n. Any combination or union for some common purpose. 
allot v. To assign a definite thing or part to a certain person. 
allotment n. Portion. 
allude v. To refer incidentally, or by suggestion. 
allusion n. An indirect and incidental reference to something without definite mention of it. 
alluvion n. Flood. 
ally n. A person or thing connected with another, usually in some relation of helpfulness. 
almanac n. A series of tables giving the days of the week together with certain astronomical information. 
aloof adv. Not in sympathy with or desiring to associate with others. 
altar n. Any raised place or structure on which sacrifices may be offered or incense burned. 
alter v. To make change in. 
alteration n. Change or modification. 
altercate v. To contend angrily or zealously in words. 
alternate n. One chosen to act in place of another, in case of the absence or incapacity of that other. 
alternative n. Something that may or must exist, be taken or chosen, or done instead of something else. 
altitude n. Vertical distance or elevation above any point or base-level, as the sea. 
alto n. The lowest or deepest female voice or part. 
altruism n. Benevolence to others on subordination to self-interest. 
altruist n. One who advocates or practices altruism. 
amalgam n. An alloy or union of mercury with another metal. 
amalgamate v. To mix or blend together in a homogeneous body. 
amateur adj. Practicing an art or occupation for the love of it, but not as a profession. 
amatory adj. Designed to excite love. 
ambidextrous adj. Having the ability of using both hands with equal skill or ease. 
ambiguous adj. Having a double meaning. 
ambitious adj. Eagerly desirous and aspiring. 
ambrosial adj. Divinely sweet, fragrant, or delicious. 
ambulance n. A vehicle fitted for conveying the sick and wounded. 
ambulate v. To walk about 
ambush n. The act or state of lying concealed for the purpose of surprising or attacking the enemy. 
ameliorate v. To relieve, as from pain or hardship 
amenable adj. Willing and ready to submit. 
Americanism n. A peculiar sense in which an English word or phrase is used in the United States. 
amicable adj. Done in a friendly spirit. 
amity n. Friendship. 
amorous adj. Having a propensity for falling in love. 
amorphous adj. Without determinate shape. 
amour n. A love-affair, especially one of an illicit nature. 
ampere n. The practical unit of electric-current strength. 
ampersand n. The character &; and. 
amphibious adj. Living both on land and in water. 
amphitheater n. An edifice of elliptical shape, constructed about a central open space or arena. 
amplitude n. Largeness. 
amply adv. Sufficiently. 
amputate v. To remove by cutting, as a limb or some portion of the body. 
amusement n. Diversion. 
anachronism n. Anything occurring or existing out of its proper time. 
anagram n. The letters of a word or phrase so transposed as to make a different word or phrase. 
analogous adj. Corresponding (to some other) in certain respects, as in form, proportion, relations. 
analogy n. Reasoning in which from certain and known relations or resemblance others are formed. 
analyst n. One who analyzes or makes use of the analytical method. 
analyze v. To examine minutely or critically. 
anarchy n. Absence or utter disregard of government. 
anathema n. Anything forbidden, as by social usage. 
anatomy n. That branch of morphology which treats of the structure of organisms. 
ancestry n. One’s ancestors collectively. 
anecdote n. A brief account of some interesting event or incident. 
anemia n. Deficiency of blood or red corpuscles. 
anemic adj. Affected with anemia. 
anemometer n. An instrument for measuring the force or velocity of wind. 
anesthetic adj. Pertaining to or producing loss of sensation. 
anew adv. Once more. 
angelic adj. Saintly. 
Anglophobia n. Hatred or dread of England or of what is English. 
Anglo-Saxon n. The entire English race wherever found, as in Europe, the United States, or India. 
angular adj. Sharp-cornered. 
anhydrous adj. Withered. 
animadversion n. The utterance of criticism or censure. 
animadvert v. To pass criticism or censure. 
animalcule n. An animal of microscopic smallness. 
animate v. To make alive. 
animosity n. Hatred. 
annalist n. Historian. 
annals n. A record of events in their chronological order, year by year. 
annex v. To add or affix at the end. 
annihilate v. To destroy absolutely. 
annotate v. To make explanatory or critical notes on or upon. 
annual adj. Occurring every year. 
annuity n. An annual allowance, payment, or income. 
annunciation n. Proclamation. 
anode n. The point where or path by which a voltaic current enters an electrolyte or the like. 
anonymous adj. Of unknown authorship. 
antagonism n. Mutual opposition or resistance of counteracting forces, principles, or persons. 
Antarctic adj. Pertaining to the south pole or the regions near it. 
ante v. In the game of poker, to put up a stake before the cards are dealt. 
antecede v. To precede. 
antecedent n. One who or that which precedes or goes before, as in time, place, rank, order, or causality. 
antechamber n. A waiting room for those who seek audience. 
antedate v. To assign or affix a date to earlier than the actual one. 
antediluvian adj. Of or pertaining to the times, things, events before the great flood in the days of Noah.
antemeridian adj. Before noon. 
antemundane adj. Pertaining to time before the world’s creation. 
antenatal adj. Occurring or existing before birth. 
anterior adj. Prior. 
anteroom n. A room situated before and opening into another, usually larger. 
anthology n. A collection of extracts from the writings of various authors. 
anthracite n. Hard coal. 
anthropology n. The science of man in general. 
anthropomorphous adj. Having or resembling human form. 
antic n. A grotesque, ludicrous, or fantastic action. 
Antichrist n. Any opponent or enemy of Christ, whether a person or a power. 
anticlimax n. A gradual or sudden decrease in the importance or impressiveness of what is said. 
anticyclone n. An atmospheric condition of high central pressure, with currents flowing outward. 
antidote n. Anything that will counteract or remove the effects of poison, disease, or the like. 
antilogy n. Inconsistency or contradiction in terms or ideas. 
antipathize v. To show or feel a feeling of antagonism, aversion, or dislike. 
antiphon n. A response or alteration of responses, generally musical. 
antiphony n. An anthem or other composition sung responsively. 
antipodes n. A place or region on the opposite side of the earth. 
antiquary n. One who collects and examines old things, as coins, books, medals, weapons, etc. 
antiquate v. To make old or out of date. 
antique adj. Pertaining to ancient times. 
antiseptic n. Anything that destroys or restrains the growth of putrefactive micro-organisms. 
antislavery adj. Opposed to human slavery. 
antispasmodic adj. Tending to prevent or relieve non-inflammatory spasmodic affections. 
antistrophe n. The inversion of terms in successive classes, as in “the home of joy and the joy of home”. 
antitoxin n. A substance which neutralizes the poisonous products of micro-organisms. 
antonym n. A word directly opposed to another in meaning. 
anxious adj. Distressed in mind respecting some uncertain matter. 
apathy n. Insensibility to emotion or passionate feeling. 
aperture n. Hole. 
apex n. The highest point, as of a mountain. 
aphorism n. Proverb. 
apiary n. A place where bees are kept. 
apogee n. The climax. 
apology n. A disclaimer of intentional error or offense. 
apostasy n. A total departure from one’s faith or religion. 
apostate adj. False. 
apostle n. Any messenger commissioned by or as by divine authority. 
apothecary n. One who keeps drugs for sale and puts up prescriptions. 
apotheosis n. Deification. 
appall v. To fill with dismay or horror. 
apparent adj. Easily understood. 
apparition n. Ghost. 
appease v. To soothe by quieting anger or indignation. 
appellate adj. Capable of being appealed to. 
appellation n. The name or title by which a particular person, class, or thing is called. 
append v. To add or attach, as something accessory, subordinate, or supplementary. 
appertain v. To belong, as by right, fitness, association, classification, possession, or natural relation. 
apposite adj. Appropriate. 
apposition n. The act of placing side by side, together, or in contact. 
appraise v. To estimate the money value of. 
appreciable adj. Capable of being discerned by the senses or intellect. 
apprehend v. To make a prisoner of (a person) in the name of the law. 
apprehensible adj. Capable of being conceived. 
approbation n. Sanction. 
appropriate adj. Suitable for the purpose and circumstances. 
aqueduct n. A water-conduit, particularly one for supplying a community from a distance. 
aqueous adj. Of, pertaining to, or containing water. 
arbiter n. One chosen or appointed, by mutual consent of parties in dispute, to decide matters. 
arbitrary adj. Fixed or done capriciously. 
arbitrate v. To act or give judgment as umpire. 
arbor n. A tree. 
arboreal adj. Of or pertaining to a tree or trees. 
arborescent adj. Having the nature of a tree. 
arboretum n. A botanical garden or place devoted to the cultivation of trees or shrubs. 
arboriculture n. The cultivation of trees or shrubs. 
arcade n. A vaulted passageway or street; a roofed passageway having shops, etc., opening from it. 
archaic adj. Antiquated 
archaism n. Obsolescence. 
archangel n. An angel of high rank. 
archbishop n. The chief of the bishops of an ecclesiastical province in the Greek, Roman, and Anglican church.
archdeacon n. A high official administrator of the affairs of a diocese. 
archaeology n. The branch of anthropology concerned with the systematic investigation of the relics of man. 
archetype n. A prototype. 
archipelago n. Any large body of water studded with islands, or the islands collectively themselves. 
ardent adj. Burning with passion. 
ardor n. Intensity of passion or affection. 
arid adj. Very dry. 
aristocracy n. A hereditary nobility 
aristocrat n. A hereditary noble or one nearly connected with nobility. 
armada n. A fleet of war-vessels. 
armful n. As much as can be held in the arm or arms. 
armory n. An arsenal. 
aroma n. An agreeable odor. 
arraign v. To call into court, as a person indicted for crime, and demand whether he pleads guilty or not.
arrange v. To put in definite or proper order. 
arrangement n. The act of putting in proper order, or the state of being put in order. 
arrant adj. Notoriously bad. 
arrear n. Something overdue and unpaid. 
arrival n. A coming to stopping-place or destination. 
arrogant adj. Unduly or excessively proud, as of wealth, station, learning, etc. 
arrogate v. To take, demand, or claim, especially presumptuously or without reasons or grounds. 
Artesian well n. A very deep bored well. water rises due to underground pressure 
artful adj. Characterized by craft or cunning. 
Arthurian adj. Pertaining to King Arthur, the real or legendary hero of British poetic story. 
artifice n. Trickery. 
artless adj. Ingenuous. 
ascendant adj. Dominant. 
ascension n. The act of rising. 
ascent n. A rising, soaring, or climbing. 
ascetic adj. Given to severe self-denial and practicing excessive abstinence and devotion. 
ascribe v. To assign as a quality or attribute. 
asexual adj. Having no distinct sexual organs. 
ashen adj. Pale. 
askance adv. With a side or indirect glance or meaning. 
asperity n. Harshness or roughness of temper. 
aspirant n. One who seeks earnestly, as for advancement, honors, place. 
aspiration n. An earnest wish for that which is above one’s present reach. 
aspire v. To have an earnest desire, wish, or longing, as for something high and good, not yet attained. 
assailant n. One who attacks. 
assassin n. One who kills, or tries to kill, treacherously or secretly. 
assassinate v. To kill, as by surprise or secret assault, especially the killing of some eminent person. 
assassination n. Murderer, as by secret assault or treachery. 
assay n. The chemical analysis or testing of an alloy ore. 
assent v. To express agreement with a statement or matter of opinion. 
assess v. To determine the amount of (a tax or other sum to be paid). 
assessor n. An officer whose duty it is to assess taxes. 
assets n. pl. Property in general, regarded as applicable to the payment of debts. 
assiduous adj. Diligent. 
assignee n. One who is appointed to act for another in the management of certain property and interests. 
assimilate v. To adapt. 
assonance n. Resemblance or correspondence in sound. 
assonant adj. Having resemblance of sound. 
assonate v. To accord in sound, especially vowel sound. 
assuage v. To cause to be less harsh, violent, or severe, as excitement, appetite, pain, or disease. 
astringent adj. Harsh in disposition or character. 
astute adj. Keen in discernment. 
atheism n. The denial of the existence of God. 
athirst adj. Wanting water. 
athwart adv. From side to side. 
atomizer n. An apparatus for reducing a liquid to a fine spray, as for disinfection, inhalation, etc. 
atone v. To make amends for. 
atonement n. Amends, reparation, or expiation made from wrong or injury. 
atrocious adj. Outrageously or wantonly wicked, criminal, vile, or cruel. 
atrocity n. Great cruelty or reckless wickedness. 
attache n. A subordinate member of a diplomatic embassy. 
attest v. To certify as accurate, genuine, or true. 
attorney-general n. The chief law-officer of a government. 
auburn adj. Reddish-brown, said usually of the hair. 
audacious adj. Fearless. 
audible adj. Loud enough to be heard. 
audition n. The act or sensation of hearing. 
auditory adj. Of or pertaining to hearing or the organs or sense of hearing. 
augment v. To make bigger. 
augur v. To predict. 
Augustinian adj. Pertaining to St. Augustine, his doctrines, or the religious orders called after him. 
aura n. Pervasive psychic influence supposed to emanate from persons 
aural adj. Of or pertaining to the ear. 
auricle n. One of the two chambers of the heart which receives the blood from the veins. 
auricular adj. Of or pertaining to the ear, its auricle, or the sense of hearing. 
auriferous adj. Containing gold. 
aurora n. A luminous phenomenon in the upper regions of the atmosphere. 
auspice n. favoring, protecting, or propitious influence or guidance. 
austere adj. Severely simple; unadorned. 
autarchy n. Unrestricted power. 
authentic adj. Of undisputed origin. 
authenticity n. The state or quality of being genuine, or of the origin and authorship claimed. 
autobiography n. The story of one’s life written by himself. 
autocracy n. Absolute government. 
autocrat n. Any one who claims or wields unrestricted or undisputed authority or influence. 
automaton n. Any living being whose actions are or appear to be involuntary or mechanical. 
autonomous adj. Self-governing. 
autonomy n. Self-government. 
autopsy n. The examination of a dead body by dissection to ascertain the cause of death. 
autumnal adj. Of or pertaining to autumn. 
auxiliary n. One who or that which aids or helps, especially when regarded as subsidiary or accessory. 
avalanche n. The fall or sliding of a mass of snow or ice down a mountain-slope, often bearing with it rock.
avarice n. Passion for getting and keeping riches. 
aver v. To assert as a fact. 
averse adj. Reluctant. 
aversion n. A mental condition of fixed opposition to or dislike of some particular thing. 
avert v. To turn away or aside. 
aviary n. A spacious cage or enclosure in which live birds are kept. 
avidity n. Greediness. 
avocation n. Diversion. 
avow v. To declare openly. 
awaken v. To arouse, as emotion, interest, or the like. 
awry adv. & adj. Out of the proper form, direction, or position. 
aye adv. An expression of assent. 
azalea n. A flowering shrub. 
azure n. The color of the sky. 
Baconian adj. Of or pertaining to Lord Bacon or his system of philosophy. 
bacterium n. A microbe. 
badger v. To pester. 
baffle v. To foil or frustrate. 
bailiff n. An officer of court having custody of prisoners under arraignment. 
baize n. A single-colored napped woolen fabric used for table-covers, curtains, etc. 
bale n. A large package prepared for transportation or storage. 
baleful adj. Malignant. 
ballad n. Any popular narrative poem, often with epic subject and usually in lyric form. 
balsam n. A medical preparation, aromatic and oily, used for healing. 
banal adj. Commonplace. 
barcarole n. A boat-song of Venetian gondoliers. 
barograph n. An instrument that registers graphically and continuously the atmospheric pressure. 
barometer n. An instrument for indicating the atmospheric pressure per unit of surface. 
barring prep. Apart from. 
baritone adj. Having a register higher than bass and lower than tenor. 
bask v. To make warm by genial heat. 
bass adj. Low in tone or compass. 
baste v. To cover with melted fat, gravy, while cooking. 
baton n. An official staff borne either as a weapon or as an emblem of authority or privilege. 
battalion n. A body of infantry composed of two or more companies, forming a part of a regiment. 
batten n. A narrow strip of wood. 
batter n. A thick liquid mixture of two or more materials beaten together, to be used in cookery. 
bauble n. A trinket. 
bawl v. To proclaim by outcry. 
beatify v. To make supremely happy. 
beatitude n. Any state of great happiness. 
beau n. An escort or lover. 
becalm v. To make quiet. 
beck v. To give a signal to, by nod or gesture. 
bedaub v. To smear over, as with something oily or sticky. 
bedeck v. To cover with ornament. 
bedlam n. Madhouse. 
befog v. To confuse. 
befriend v. To be a friend to, especially when in need. 
beget v. To produce by sexual generation. 
begrudge v. To envy one of the possession of. 
belate v. To delay past the proper hour. 
belay v. To make fast, as a rope, by winding round a cleat. 
belie v. To misrepresent. 
believe v. To accept as true on the testimony or authority of others. 
belittle v. To disparage. 
belle n. A woman who is a center of attraction because of her beauty, accomplishments, etc. 
bellicose adj. Warlike. 
belligerent adj. Manifesting a warlike spirit. 
bemoan v. To lament 
benediction n. a solemn invocation of the divine blessing. 
benefactor n. A doer of kindly and charitable acts. 
benefice n. A church office endowed with funds or property for the maintenance of divine service. 
beneficent adj. Characterized by charity and kindness. 
beneficial adj. Helpful. 
beneficiary n. One who is lawfully entitled to the profits and proceeds of an estate or property. 
benefit n. Helpful result. 
benevolence n. Any act of kindness or well-doing. 
benevolent adj. Loving others and actively desirous of their well-being. 
benign adj. Good and kind of heart. 
benignant adj. Benevolent in feeling, character, or aspect. 
benignity n. Kindness of feeling, disposition, or manner. 
benison n. Blessing. 
bequeath v. To give by will. 
bereave v. To make desolate with loneliness and grief. 
berth n. A bunk or bed in a vessel, sleeping-car, etc. 
beseech v. To implore. 
beset v. To attack on all sides. 
besmear v. To smear over, as with any oily or sticky substance. 
bestial adj. Animal. 
bestrew v. To sprinkle or cover with things strewn. 
bestride v. To get or sit upon astride, as a horse. 
bethink v. To remind oneself. 
betide v. To happen to or befall. 
betimes adv. In good season or time. 
betroth v. To engage to marry. 
betrothal n. Engagement to marry. 
bevel n. Any inclination of two surfaces other than 90 degrees. 
bewilder v. To confuse the perceptions or judgment of. 
bibliomania n. The passion for collecting books. 
bibliography n. A list of the words of an author, or the literature bearing on a particular subject. 
bibliophile n. One who loves books. 
bibulous adj. Fond of drinking. 
bide v. To await. 
biennial n. A plant that produces leaves and roots the first year and flowers and fruit the second. 
bier n. A horizontal framework with two handles at each end for carrying a corpse to the grave. 
bigamist n. One who has two spouses at the same time. 
bigamy n. The crime of marrying any other person while having a legal spouse living. 
bight n. A slightly receding bay between headlands, formed by a long curve of a coast-line. 
bilateral adj. Two-sided. 
bilingual adj. Speaking two languages. 
biograph n. A bibliographical sketch or notice. 
biography n. A written account of one’s life, actions, and character. 
biology n. The science of life or living organisms. 
biped n. An animal having two feet. 
birthright n. A privilege or possession into which one is born. 
bitterness n. Acridity, as to the taste. 
blase adj. Sated with pleasure. 
blaspheme v. To indulge in profane oaths. 
blatant adj. Noisily or offensively loud or clamorous. 
blaze n. A vivid glowing flame. 
blazon v. To make widely or generally known. 
bleak adj. Desolate. 
blemish n. A mark that mars beauty. 
blithe adj. Joyous. 
blithesome adj. Cheerful. 
blockade n. The shutting up of a town, a frontier, or a line of coast by hostile forces. 
boatswain n. A subordinate officer of a vessel, who has general charge of the rigging, anchors, etc. 
bodice n. A women’s ornamental corset-shaped laced waist. 
bodily adj. Corporeal. 
boisterous adj. Unchecked merriment or animal spirits. 
bole n. The trunk or body of a tree. 
bolero n. A Spanish dance, illustrative of the passion of love, accompanied by caste nets and singing. 
boll n. A round pod or seed-capsule, as a flax or cotton. 
bolster v. To support, as something wrong. 
bomb n. A hollow projectile containing an explosive material. 
bombard v. To assail with any missile or with abusive speech. 
bombardier n. A person who has charge of mortars, bombs, and shells. 
bombast n. Inflated or extravagant language, especially on unimportant subjects. 
boorish adj. Rude. 
bore v. To weary by tediousness or dullness. 
borough n. An incorporated village or town. 
bosom n. The breast or the upper front of the thorax of a human being, especially of a woman. 
botanical adj. Connected with the study or cultivation of plants. 
botanize v. To study plant-life. 
botany n. The science that treats of plants. 
bountiful adj. Showing abundance. 
Bowdlerize v. To expurgate in editing (a literary composition) by omitting words or passages. 
bowler n. In cricket, the player who delivers the ball. 
boycott v. To place the products or merchandise of under a ban. 
brae n. Hillside. 
braggart n. A vain boaster. 
brandish v. To wave, shake, or flourish triumphantly or defiantly, as a sword or spear. 
bravado n. An aggressive display of boldness. 
bravo interj. Well done. 
bray n. A loud harsh sound, as the cry of an ass or the blast of a horn. 
braze v. To make of or ornament with brass. 
brazier n. An open pan or basin for holding live coals. 
breach n. The violation of official duty, lawful right, or a legal obligation. 
breaker n. One who trains horses, dogs, etc. 
breech n. The buttocks. 
brethren n. pl. Members of a brotherhood, gild, profession, association, or the like. 
brevity n. Shortness of duration. 
bric-a-brac n. Objects of curiosity or for decoration. 
bridle n. The head-harness of a horse consisting of a head-stall, a bit, and the reins. 
brigade n. A body of troops consisting of two or more regiments. 
brigadier n. General officer who commands a brigade, ranking between a colonel and a major-general. 
brigand n. One who lives by robbery and plunder. 
brimstone n. Sulfur. 
brine n. Water saturated with salt. 
bristle n. One of the coarse, stiff hairs of swine: used in brush-making, etc. 
Britannia n. The United Kingdom of Great Britain. 
Briticism n. A word, idiom, or phrase characteristic of Great Britain or the British. 
brittle adj. Fragile. 
broach v. To mention, for the first time. 
broadcast adj. Disseminated far and wide. 
brogan n. A coarse, heavy shoe. 
brogue n. Any dialectic pronunciation of English, especially that of the Irish people. 
brokerage n. The business of making sales and purchases for a commission; a broker. 
bromine n. A dark reddish-brown, non-metallic liquid element with a suffocating odor. 
bronchitis n. Inflammation of the bronchial tubes. 
bronchus n. Either of the two subdivisions of the trachea conveying air into the lungs. 
brooch n. An article of jewelry fastened by a hinged pin and hook on the underside. 
brotherhood n. Spiritual or social fellowship or solidarity. 
browbeat v. To overwhelm, or attempt to do so, by stern, haughty, or rude address or manner. 
brusque adj. Somewhat rough or rude in manner or speech. 
buffoon n. A clown. 
buffoonery n. Low drollery, coarse jokes, etc. 
bulbous adj. Of, or pertaining to, or like a bulb. 
bullock n. An ox. 
bulrush n. Any one of various tall rush-like plants growing in damp ground or water. 
bulwark n. Anything that gives security or defense. 
bumper n. A cup or glass filled to the brim, especially one to be drunk as a toast or health. 
bumptious adj. Full of offensive and aggressive self-conceit. 
bungle v. To execute clumsily. 
buoyancy n. Power or tendency to float on or in a liquid or gas. 
buoyant adj. Having the power or tendency to float or keep afloat. 
bureau n. A chest of drawers for clothing, etc. 
bureaucracy n. Government by departments of men transacting particular branches of public business. 
burgess n. In colonial times, a member of the lower house of the legislature of Maryland or Virginia. 
burgher n. An inhabitant, citizen or freeman of a borough burgh, or corporate town. 
burnish v. To make brilliant or shining. 
bursar n. A treasurer. 
bustle v. To hurry. 
butt v. To strike with or as with the head, or horns. 
butte n. A conspicuous hill, low mountain, or natural turret, generally isolated. 
buttress n. Any support or prop. 
by-law n. A rule or law adopted by an association, a corporation, or the like. 
cabal n. A number of persons secretly united for effecting by intrigue some private purpose. 
cabalism n. Superstitious devotion to one’s religion. 
cabinet n. The body of men constituting the official advisors of the executive head of a nation. 
cacophony n. A disagreeable, harsh, or discordant sound or combination of sounds or tones. 
cadaverous adj. Resembling a corpse. 
cadence n. Rhythmical or measured flow or movement, as in poetry or the time and pace of marching troops. 
cadenza n. An embellishment or flourish, prepared or improvised, for a solo voice or instrument. 
caitiff adj. Cowardly. 
cajole v. To impose on or dupe by flattering speech. 
cajolery n. Delusive speech. 
calculable adj. That may be estimated by reckoning. 
calculus n. A concretion formed in various parts of the body resembling a pebble in hardness. 
callosity n. The state of being hard and insensible. 
callow adj. Without experience of the world. 
calorie n. Amount of heat needed to raise the temperature of 1 kilogram of water 1 degree centigrade. 
calumny n. Slander. 
Calvary n. The place where Christ was crucified. 
Calvinism n. The system of doctrine taught by John Calvin. 
Calvinize v. To teach or imbue with the doctrines of Calvinism. 
came n. A leaden sash-bar or grooved strip for fastening panes in stained-glass windows. 
cameo n. Any small engraved or carved work in relief. 
campaign n. A complete series of connected military operations. 
Canaanite n. A member of one of the three tribes that dwelt in the land of Canaan, or western Palestine. 
canary adj. Of a bright but delicate yellow. 
candid adj. Straightforward. 
candor n. The quality of frankness or outspokenness. 
canine adj. Characteristic of a dog. 
canon n. Any rule or law. 
cant v. To talk in a singsong, preaching tone with affected solemnity. 
cantata n. A choral composition. 
canto n. One of the divisions of an extended poem. 
cantonment n. The part of the town or district in which the troops are quartered. 
capacious adj. Roomy. 
capillary n. A minute vessel having walls composed of a single layer of cells. 
capitulate v. To surrender or stipulate terms. 
caprice n. A whim. 
caption n. A heading, as of a chapter, section, document, etc. 
captious adj. Hypercritical. 
captivate v. To fascinate, as by excellence. eloquence, or beauty. 
carcass n. The dead body of an animal. 
cardiac adj. Pertaining to the heart. 
cardinal adj. Of prime or special importance. 
caret n. A sign (^) placed below a line, indicating where omitted words, etc., should be inserted. 
caricature n. a picture or description in which natural characteristics are exaggerated or distorted. 
carnage n. Massacre. 
carnal adj. Sensual. 
carnivorous adj. Eating or living on flesh. 
carouse v. To drink deeply and in boisterous or jovial manner. 
carrion n. Dead and putrefying flesh. 
cartilage n. An elastic animal tissue of firm consistence. 
cartridge n. A charge for a firearm, or for blasting. 
caste n. The division of society on artificial grounds. 
castigate v. To punish. 
casual adj. Accidental, by chance. 
casualty n. A fatal or serious accident or disaster. 
cataclysm n. Any overwhelming flood of water. 
cataract n. Opacity of the lens of the eye resulting in complete or partial blindness. 
catastrophe n. Any great and sudden misfortune or calamity. 
cathode n. The negative pole or electrode of a galvanic battery. 
Catholicism n. The system, doctrine, and practice of the Roman Catholic Church. 
catholicity n. Universal prevalence or acceptance. 
cat-o-nine-tails n. An instrument consisting of nine pieces of cord, formerly used for flogging in the army and navy. 
caucus n. A private meeting of members of a political party to select candidates. 
causal adj. Indicating or expressing a cause. 
caustic adj. Sarcastic and severe. 
cauterize v. To burn or sear as with a heated iron. 
cede v. To pass title to. 
censor n. An official examiner of manuscripts empowered to prohibit their publication. 
censorious adj. Judging severely or harshly. 
census n. An official numbering of the people of a country or district. 
centenary adj. Pertaining to a hundred years or a period of a hundred years. 
centiliter n. A hundredth of a liter. 
centimeter n. A length of one hundredth of a meter. 
centurion n. A captain of a company of one hundred infantry in the ancient Roman army. 
cereal adj. Pertaining to edible grain or farinaceous seeds. 
ceremonial adj. Characterized by outward form or ceremony. 
ceremonious adj. Observant of ritual. 
cessation n. Discontinuance, as of action or motion. 
cession n. Surrender, as of possessions or rights. 
chagrin n. Keen vexation, annoyance, or mortification, as at one’s failures or errors. 
chameleon adj. Changeable in appearance. 
chancery n. A court of equity, as distinguished from a common-law court. 
chaos n. Any condition of which the elements or parts are in utter disorder and confusion. 
characteristic n. A distinctive feature. 
characterize v. To describe by distinctive marks or peculiarities. 
charlatan n. A quack. 
chasm n. A yawning hollow, as in the earth’s surface. 
chasten v. To purify by affliction. 
chastise v. To subject to punitive measures. 
chastity n. Sexual or moral purity. 
chateau n. A castle or manor-house. 
chattel n. Any article of personal property. 
check v. To hold back. 
chiffon n. A very thin gauze used for trimmings, evening dress, etc. 
chivalry n. The knightly system of feudal times with its code, usages and practices. 
cholera n. An acute epidemic disease. 
choleric adj. Easily provoked to anger. 
choral adj. Pertaining to, intended for, or performed by a chorus or choir. 
Christ n. A title of Jesus 
christen v. To name in baptism. 
Christendom n. That part of the world where Christianity is generally professed. 
chromatic adj. Belonging, relating to, or abounding in color. 
chronology n. The science that treats of computation of time or of investigation and arrangement of events. 
chronometer n. A portable timekeeper of the highest attainable precision. 
cipher v. To calculate arithmetically. (also a noun meaning zero or nothing) 
circulate v. To disseminate. 
circumference n. The boundary-line of a circle. 
circumlocution n. Indirect or roundabout expression. 
circumnavigate v. To sail quite around. 
circumscribe v. To confine within bounds. 
circumspect adj. Showing watchfulness, caution, or careful consideration. 
citadel n. Any strong fortress. 
cite v. To refer to specifically. 
claimant n. One who makes a claim or demand, as of right. 
clairvoyance n. Intuitive sagacity or perception. 
clamorous adj. Urgent in complaint or demand. 
clan n. A tribe. 
clandestine adj. Surreptitious. 
clangor n. Clanking or a ringing, as of arms, chains, or bells; clamor. 
clarify v. To render intelligible. 
clarion n. A small shrill trumpet or bugle. 
classify v. To arrange in a class or classes on the basis of observed resemblance’s and differences. 
clearance n. A certificate from the proper authorities that a vessel has complied with the law and may sail. 
clemency n. Mercy. 
clement adj. Compassionate. 
close-hauled adj. Having the sails set for sailing as close to the wind as possible. 
clothier n. One who makes or sells cloth or clothing. 
clumsy adj. Awkward of movement. 
coagulate v. To change into a clot or a jelly, as by heat, by chemical action, or by a ferment. 
coagulant adj. Producing coagulation. 
coalescence n. The act or process of coming together so as to form one body, combination, or product. 
coalition n. Combination in a body or mass. 
coddle v. To treat as a baby or an invalid. 
codicil n. A supplement adding to, revoking, or explaining in the body of a will. 
coerce v. To force. 
coercion n. Forcible constraint or restraint, moral or physical. 
coercive adj. Serving or tending to force. 
cogent adj. Appealing strongly to the reason or conscience. 
cognate adj. Akin. 
cognizant adj. Taking notice. 
cohere v. To stick together. 
cohesion n. Consistency. 
cohesive adj. Having the property of consistency. 
coincide v. To correspond. 
coincidence n. A circumstance so agreeing with another: often implying accident. 
coincident adj. Taking place at the same time. 
collaborate v. To labor or cooperate with another or others, especially in literary or scientific pursuits. 
collapse v. To cause to shrink, fall in, or fail. 
collapsible adj. That may or can collapse. 
colleague n. An associate in professional employment. 
collective adj. Consisting of a number of persons or objects considered as gathered into a mass, or sum. 
collector n. One who makes a collection, as of objects of art, books, or the like. 
collegian n. A college student. 
collide v. To meet and strike violently. 
collier n. One who works in a coal-mine. 
collision n. Violent contact. 
colloquial adj. Pertaining or peculiar to common speech as distinguished from literary. 
colloquialism n. Form of speech used only or chiefly in conversation. 
colloquy n. Conversation. 
collusion n. A secret agreement for a wrongful purpose. 
colossus n. Any strikingly great person or object. 
comely adj. Handsome. 
comestible adj. Fit to be eaten. 
comical adj. Funny. 
commemorate v. To serve as a remembrance of. 
commentary n. A series of illustrative or explanatory notes on any important work. 
commingle v. To blend. 
commissariat n. The department of an army charged with the provision of its food and water and daily needs. 
commission v. To empower. 
commitment n. The act or process of entrusting or consigning for safe-keeping. 
committal n. The act, fact, or result of committing, or the state of being 
commodity n. Something that is bought and sold. 
commotion n. A disturbance or violent agitation. 
commute v. To put something, especially something less severe, in place of. 
comparable adj. Fit to be compared. 
comparative adj. Relative. 
comparison n. Examination of two or more objects with reference to their likeness or unlikeness. 
compensate v. To remunerate. 
competence n. Adequate qualification or capacity. 
competent adj. Qualified. 
competitive adj. characterized by rivalry. 
competitor n. A rival. 
complacence n. Satisfaction with one’s acts or surroundings. 
complacent adj. Pleased or satisfied with oneself. 
complaisance n. Politeness. 
complaisant adj. Agreeable. 
complement v. To make complete. 
complex adj. Complicated. 
compliant adj. Yielding. 
complicate v. To make complex, difficult, or hard to deal with. 
complication n. An intermingling or combination of things or parts, especially in a perplexing manner. 
complicity n. Participation or partnership, as in wrong-doing or with a wrong-doer. 
compliment v. To address or gratify with expressions of delicate praise. 
component n. A constituent element or part. 
comport v. To conduct or behave (oneself). 
composure n. Calmness. 
comprehensible adj. Intelligible. 
comprehension n. Ability to know. 
comprehensive adj. Large in scope or content. 
compress v. To press together or into smaller space. 
compressible adj. Capable of being pressed into smaller compass. 
compression n. Constraint, as by force or authority. 
comprise v. To consist of. 
compulsion n. Coercion. 
compulsory adj. Forced. 
compunction n. Remorseful feeling. 
compute v. To ascertain by mathematical calculation. 
concede v. To surrender. 
conceit n. Self-flattering opinion. 
conceive v. To form an idea, mental image or thought of. 
concerto n. A musical composition. 
concession n. Anything granted or yielded, or admitted in response to a demand, petition, or claim. 
conciliate v. To obtain the friendship of. 
conciliatory adj. Tending to reconcile. 
conclusive adj. Sufficient to convince or decide. 
concord n. Harmony. 
concordance n. Harmony. 
concur v. To agree. 
concurrence n. Agreement. 
concurrent adj. Occurring or acting together. 
concussion n. A violent shock to some organ by a fall or a sudden blow. 
condensation n. The act or process of making dense or denser. 
condense v. To abridge. 
condescend v. To come down voluntarily to equal terms with inferiors. 
condolence n. Expression of sympathy with a person in pain, sorrow, or misfortune. 
conduce v. To bring about. 
conducive adj. Contributing to an end. 
conductible adj. Capable of being conducted or transmitted. 
conduit n. A means for conducting something, particularly a tube, pipe, or passageway for a fluid. 
confectionery n. The candy collectively that a confectioner makes or sells, as candy. 
confederacy n. A number of states or persons in compact or league with each other, as for mutual aid. 
confederate n. One who is united with others in a league, compact, or agreement. 
confer v. To bestow. 
conferee n. A person with whom another confers. 
confessor n. A spiritual advisor. 
confidant n. One to whom secrets are entrusted. 
confide v. To reveal in trust or confidence. 
confidence n. The state or feeling of trust in or reliance upon another. 
confident adj. Assured. 
confinement n. Restriction within limits or boundaries. 
confiscate v. To appropriate (private property) as forfeited to the public use or treasury. 
conflagration n. A great fire, as of many buildings, a forest, or the like. 
confluence n. The place where streams meet. 
confluent n. A stream that unites with another. 
conformance n. The act or state or conforming. 
conformable adj. Harmonious. 
conformation n. General structure, form, or outline. 
conformity n. Correspondence in form, manner, or use. 
confront v. To encounter, as difficulties or obstacles. 
congeal v. To coagulate. 
congenial adj. Having kindred character or tastes. 
congest v. To collect into a mass. 
congregate v. To bring together into a crowd. 
coniferous adj. Cone-bearing trees. 
conjecture n. A guess. 
conjoin v. To unite. 
conjugal adj. Pertaining to marriage, marital rights, or married persons. 
conjugate adj. Joined together in pairs. 
conjugation n. The state or condition of being joined together. 
conjunction n. The state of being joined together, or the things so joined. 
connive v. To be in collusion. 
connoisseur n. A critical judge of art, especially one with thorough knowledge and sound judgment of art. 
connote v. To mean; signify. 
connubial adj. Pertaining to marriage or matrimony. 
conquer v. To overcome by force. 
consanguineous adj. Descended from the same parent or ancestor. 
conscience n. The faculty in man by which he distinguishes between right and wrong in character and conduct. 
conscientious adj. Governed by moral standard. 
conscious adj. Aware that one lives, feels, and thinks. 
conscript v. To force into military service. 
consecrate v. To set apart as sacred. 
consecutive adj. Following in uninterrupted succession. 
consensus n. A collective unanimous opinion of a number of persons. 
conservatism n. Tendency to adhere to the existing order of things. 
conservative adj. Adhering to the existing order of things. 
conservatory n. An institution for instruction and training in music and declamation. 
consign v. To entrust. 
consignee n. A person to whom goods or other property has been entrusted. 
consignor n. One who entrusts. 
consistency n. A state of permanence. 
console v. To comfort. 
consolidate v. To combine into one body or system. 
consonance n. The state or quality of being in accord with. 
consonant adj. Being in agreement or harmony with. 
consort n. A companion or associate. 
conspicuous adj. Clearly visible. 
conspirator n. One who agrees with others to cooperate in accomplishing some unlawful purpose. 
conspire v. To plot. 
constable n. An officer whose duty is to maintain the peace. 
constellation n. An arbitrary assemblage or group of stars. 
consternation n. Panic. 
constituency n. The inhabitants or voters in a district represented in a legislative body. 
constituent n. One who has the right to vote at an election. 
constrict v. To bind. 
consul n. An officer appointed to reside in a foreign city, chiefly to represent his country. 
consulate n. The place in which a consul transacts official business. 
consummate v. To bring to completion. 
consumption n. Gradual destruction, as by burning, eating, etc., or by using up, wearing out, etc. 
consumptive adj. Designed for gradual destruction. 
contagion n. The communication of disease from person to person. 
contagious adj. Transmitting disease. 
contaminate v. To pollute. 
contemplate v. To consider thoughtfully. 
contemporaneous adj. Living, occurring, or existing at the same time. 
contemporary adj. Living or existing at the same time. 
contemptible adj. Worthy of scorn or disdain. 
contemptuous adj. Disdainful. 
contender n. One who exerts oneself in opposition or rivalry. 
contiguity n. Proximity. 
contiguous adj. Touching or joining at the edge or boundary. 
continence n. Self-restraint with respect to desires, appetites, and passion. 
contingency n. Possibility of happening. 
contingent adj. Not predictable. 
continuance n. Permanence. 
continuation n. Prolongation. 
continuity n. Uninterrupted connection in space, time, operation, or development. 
continuous adj. Connected, extended, or prolonged without separation or interruption of sequence. 
contort v. To twist into a misshapen form. 
contraband n. Trade forbidden by law or treaty. 
contradiction n. The assertion of the opposite of that which has been said. 
contradictory adj. Inconsistent with itself. 
contraposition n. A placing opposite. 
contravene v. To prevent or obstruct the operation of. 
contribution n. The act of giving for a common purpose. 
contributor n. One who gives or furnishes, in common with others, for a common purpose. 
contrite adj. Broken in spirit because of a sense of sin. 
contrivance n. The act planning, devising, inventing, or adapting something to or for a special purpose. 
contrive v. To manage or carry through by some device or scheme. 
control v. To exercise a directing, restraining, or governing influence over. 
controller n. One who or that which regulates or directs. 
contumacious adj. Rebellious. 
contumacy n. Contemptuous disregard of the requirements of rightful authority. 
contuse v. To bruise by a blow, either with or without the breaking of the skin. 
contusion n. A bruise. 
convalesce v. To recover after a sickness. 
convalescence n. The state of progressive restoration to health and strength after the cessation of disease. 
convalescent adj. Recovering health after sickness. 
convene v. To summon or cause to assemble. 
convenience n. Fitness, as of time or place. 
converge v. To cause to incline and approach nearer together. 
convergent adj. Tending to one point. 
conversant adj. Thoroughly informed. 
conversion n. Change from one state or position to another, or from one form to another. 
convertible adj. Interchangeable. 
convex adj. Curving like the segment of the globe or of the surface of a circle. 
conveyance n. That by which anything is transported. 
convivial adj. Devoted to feasting, or to good-fellowship in eating or drinking. 
convolution n. A winding motion. 
convolve v. To move with a circling or winding motion. 
convoy n. A protecting force accompanying property in course of transportation. 
convulse v. To cause spasms in. 
convulsion n. A violent and abnormal muscular contraction of the body. 
copious adj. Plenteous. 
coquette n. A flirt. 
cornice n. An ornamental molding running round the walls of a room close to the ceiling. 
cornucopia n. The horn of plenty, symbolizing peace and prosperity. 
corollary n. A proposition following so obviously from another that it requires little demonstration. 
coronation n. The act or ceremony of crowning a monarch. 
coronet n. Inferior crown denoting, according to its form, various degrees of noble rank less than sovereign.
corporal adj. Belonging or relating to the body as opposed to the mind. 
corporate adj. Belonging to a corporation. 
corporeal adj. Of a material nature; physical. 
corps n. A number or body of persons in some way associated or acting together. 
corpse n. A dead body. 
corpulent adj. Obese. 
corpuscle n. A minute particle of matter. 
correlate v. To put in some relation of connection or correspondence. 
correlative adj. Mutually involving or implying one another. 
corrigible adj. Capable of reformation. 
corroborate v. To strengthen, as proof or conviction. 
corroboration n. Confirmation. 
corrode v. To ruin or destroy little by little. 
corrosion n. Gradual decay by crumbling or surface disintegration. 
corrosive n. That which causes gradual decay by crumbling or surface disintegration. 
corruptible adj. Open to bribery. 
corruption n. Loss of purity or integrity. 
cosmetic adj. Pertaining to the art of beautifying, especially the complexion. 
cosmic adj. Pertaining to the universe. 
cosmogony n. A doctrine of creation or of the origin of the universe. 
cosmography n. The science that describes the universe, including astronomy, geography, and geology. 
cosmology n. The general science of the universe. 
cosmopolitan adj. Common to all the world. 
cosmopolitanism n. A cosmopolitan character. 
cosmos n. The world or universe considered as a system, perfect in order and arrangement. 
counter-claim n. A cross-demand alleged by a defendant in his favor against the plaintiff. 
counteract v. To act in opposition to. 
counterbalance v. To oppose with an equal force. 
countercharge v. To accuse in return. 
counterfeit adj. Made to resemble something else. 
counterpart n. Something taken with another for the completion of either. 
countervail v. To offset. 
counting-house n. A house or office used for transacting business, bookkeeping, correspondence, etc. 
countryman n. A rustic. 
courageous adj. Brave. 
course n. Line of motion or direction. 
courser n. A fleet and spirited horse. 
courtesy n. Politeness originating in kindness and exercised habitually. 
covenant n. An agreement entered into by two or more persons or parties. 
covert adj. Concealed, especially for an evil purpose. 
covey n. A flock of quails or partridges. 
cower v. To crouch down tremblingly, as through fear or shame. 
coxswain n. One who steers a rowboat, or one who has charge of a ship’s boat and its crew under an officer. 
crag n. A rugged, rocky projection on a cliff or ledge. 
cranium n. The skull of an animal, especially that part enclosing the brain. 
crass adj. Coarse or thick in nature or structure, as opposed to thin or fine. 
craving n. A vehement desire. 
creak n. A sharp, harsh, squeaking sound. 
creamery n. A butter-making establishment. 
creamy adj. Resembling or containing cream. 
credence n. Belief. 
credible adj. Believable. 
credulous adj. Easily deceived. 
creed n. A formal summary of fundamental points of religious belief. 
crematory adj. A place for cremating dead bodies. 
crevasse n. A deep crack or fissure in the ice of a glacier. 
crevice n. A small fissure, as between two contiguous surfaces. 
criterion n. A standard by which to determine the correctness of a judgment or conclusion. 
critique n. A criticism or critical review. 
crockery n. Earthenware made from baked clay. 
crucible n. A trying and purifying test or agency. 
crusade n. Any concerted movement, vigorously prosecuted, in behalf of an idea or principle. 
crustacean adj. Pertaining to a division of arthropods, containing lobsters, crabs, crawfish, etc. 
crustaceous adj. Having a crust-like shell. 
cryptogram n. Anything written in characters that are secret or so arranged as to have hidden meaning. 
crystallize v. To bring together or give fixed shape to. 
cudgel n. A short thick stick used as a club. 
culinary adj. Of or pertaining to cooking or the kitchen. 
cull v. To pick or sort out from the rest. 
culpable adj. Guilty. 
culprit n. A guilty person. 
culvert n. Any artificial covered channel for the passage of water through a bank or under a road, canal. 
cupidity n. Avarice. 
curable adj. Capable of being remedied or corrected. 
curator n. A person having charge as of a library or museum. 
curio n. A piece of bric-a-brac. 
cursive adj. Writing in which the letters are joined together. 
cursory adj. Rapid and superficial. 
curt adj. Concise, compressed, and abrupt in act or expression. 
curtail v. To cut off or cut short. 
curtsy n. A downward movement of the body by bending the knees. 
cycloid adj. Like a circle. 
cygnet n. A young swan. 
cynical adj. Exhibiting moral skepticism. 
cynicism n. Contempt for the opinions of others and of what others value. 
cynosure n. That to which general interest or attention is directed. 
daring adj. Brave. 
darkling adv. Blindly. 
Darwinism n. The doctrine that natural selection has been the prime cause of evolution of higher forms. 
dastard n. A base coward. 
datum n. A premise, starting-point, or given fact. 
dauntless adj. Fearless. 
day-man n. A day-laborer. 
dead-heat n. A race in which two or more competitors come out even, and there is no winner. 
dearth n. Scarcity, as of something customary, essential ,or desirable. 
death’s-head n. A human skull as a symbol of death. 
debase v. To lower in character or virtue. 
debatable adj. Subject to contention or dispute. 
debonair adj. Having gentle or courteous bearing or manner. 
debut n. A first appearance in society or on the stage. 
decagon n. A figure with ten sides and ten angles. 
decagram n. A weight of 10 grams. 
decaliter n. A liquid and dry measure of 10 liters. 
decalogue n. The ten commandments. 
Decameron n. A volume consisting of ten parts or books. 
decameter n. A length of ten meters. 
decamp v. To leave suddenly or unexpectedly. 
decapitate v. To behead. 
decapod adj. Ten-footed or ten-armed. 
decasyllable n. A line of ten syllables. 
deceit n. Falsehood. 
deceitful adj. Fraudulent. 
deceive v. To mislead by or as by falsehood. 
decency n. Moral fitness. 
decent adj. Characterized by propriety of conduct, speech, manners, or dress. 
deciduous adj. Falling off at maturity as petals after flowering, fruit when ripe, etc. 
decimal adj. Founded on the number 10. 
decimate v. To destroy a measurable or large proportion of. 
decipher v. To find out the true words or meaning of, as something hardly legible. 
decisive ad. Conclusive. 
declamation n. A speech recited or intended for recitation from memory in public. 
declamatory adj. A full and formal style of utterance. 
declarative adj. Containing a formal, positive, or explicit statement or affirmation. 
declension n. The change of endings in nouns and adj. to express their different relations of gender. 
decorate v. To embellish. 
decorous adj. Suitable for the occasion or circumstances. 
decoy n. Anything that allures, or is intended to allures into danger or temptation. 
decrepit adj. Enfeebled, as by old age or some chronic infirmity. 
dedication n. The voluntary consecration or relinquishment of something to an end or cause. 
deduce v. To derive or draw as a conclusion by reasoning from given premises or principles. 
deface v. To mar or disfigure the face or external surface of. 
defalcate v. To cut off or take away, as a part of something. 
defamation n. Malicious and groundless injury done to the reputation or good name of another. 
defame v. To slander. 
default n. The neglect or omission of a legal requirement. 
defendant n. A person against whom a suit is brought. 
defensible adj. Capable of being maintained or justified. 
defensive adj. Carried on in resistance to aggression. 
defer v. To delay or put off to some other time. 
deference n. Respectful submission or yielding, as to another’s opinion, wishes, or judgment. 
defiant adj. Characterized by bold or insolent opposition. 
deficiency n. Lack or insufficiency. 
deficient adj. Not having an adequate or proper supply or amount. 
definite adj. Having an exact signification or positive meaning. 
deflect v. To cause to turn aside or downward. 
deforest v. To clear of forests. 
deform v. To disfigure. 
deformity n. A disfigurement. 
defraud v. To deprive of something dishonestly. 
defray v. To make payment for. 
degeneracy n. A becoming worse. 
degenerate v. To become worse or inferior. 
degradation n. Diminution, as of strength or magnitude. 
degrade v. To take away honors or position from. 
dehydrate v. To deprive of water. 
deify v. To regard or worship as a god. 
deign v. To deem worthy of notice or account. 
deist n. One who believes in God, but denies supernatural revelation. 
deity n. A god, goddess, or divine person. 
deject v. To dishearten. 
dejection n. Melancholy. 
delectable adj. Delightful to the taste or to the senses. 
delectation n. Delight. 
deleterious adj. Hurtful, morally or physically. 
delicacy n. That which is agreeable to a fine taste. 
delineate v. To represent by sketch or diagram. 
deliquesce v. To dissolve gradually and become liquid by absorption of moisture from the air. 
delirious adj. Raving. 
delude v. To mislead the mind or judgment of. 
deluge v. To overwhelm with a flood of water. 
delusion n. Mistaken conviction, especially when more or less enduring. 
demagnetize v. To deprive (a magnet) of magnetism. 
demagogue n. An unprincipled politician. 
demeanor n. Deportment. 
demented adj. Insane. 
demerit n. A mark for failure or bad conduct. 
demise n. Death. 
demobilize v. To disband, as troops. 
demolish v. To annihilate. 
demonstrable adj. Capable of positive proof. 
demonstrate v. To prove indubitably. 
demonstrative adj. Inclined to strong exhibition or expression of feeling or thoughts. 
demonstrator n. One who proves in a convincing and conclusive manner. 
demulcent n. Any application soothing to an irritable surface 
demurrage n. the detention of a vessel beyond the specified time of sailing. 
dendroid adj. Like a tree. 
dendrology n. The natural history of trees. 
denizen n. Inhabitant. 
denominate v. To give a name or epithet to. 
denomination n. A body of Christians united by a common faith and form of worship and discipline. 
denominator n. Part of a fraction which expresses the number of equal parts into which the unit is divided. 
denote v. To designate by word or mark. 
denouement n. That part of a play or story in which the mystery is cleared up. 
denounce v. To point out or publicly accuse as deserving of punishment, censure, or odium. 
dentifrice n. Any preparation used for cleaning the teeth. 
denude v. To strip the covering from. 
denunciation n. The act of declaring an action or person worthy of reprobation or punishment. 
deplete v. To reduce or lessen, as by use, exhaustion, or waste. 
deplorable adj. Contemptible. 
deplore v. To regard with grief or sorrow. 
deponent adj. Laying down. 
depopulate v. To remove the inhabitants from. 
deport v. To take or send away forcibly, as to a penal colony. 
deportment n. Demeanor. 
deposition n. Testimony legally taken on interrogatories and reduced to writing, for use as evidence in court.
depositor n. One who makes a deposit, or has an amount deposited. 
depository n. A place where anything is kept in safety. 
deprave v. To render bad, especially morally bad. 
deprecate v. To express disapproval or regret for, with hope for the opposite. 
depreciate v. To lessen the worth of. 
depreciation n. A lowering in value or an underrating in worth. 
depress v. To press down. 
depression n. A falling of the spirits. 
depth n. Deepness. 
derelict adj. Neglectful of obligation. 
deride v. To ridicule. 
derisible adj. Open to ridicule. 
derision n. Ridicule. 
derivation n. That process by which a word is traced from its original root or primitive form and meaning. 
derivative adj. Coming or acquired from some origin. 
derive v. To deduce, as from a premise. 
dermatology n. The branch of medical science which relates to the skin and its diseases. 
derrick n. An apparatus for hoisting and swinging great weights. 
descendant n. One who is descended lineally from another, as a child, grandchild, etc. 
descendent adj. Proceeding downward. 
descent n. The act of moving or going downward. 
descry v. To discern. 
desert v. To abandon without regard to the welfare of the abandoned
desiccant n. Any remedy which, when applied externally, dries up or absorbs moisture, as that of wounds. 
designate v. To select or appoint, as by authority. 
desist v. To cease from action. 
desistance n. Cessation. 
despair n. Utter hopelessness and despondency. 
desperado n. One without regard for law or life. 
desperate adj. Resorted to in a last extremity, or as if prompted by utter despair. 
despicable adj. Contemptible. 
despite prep. In spite of. 
despond v. To lose spirit, courage, or hope. 
despondent adj. Disheartened. 
despot n. An absolute and irresponsible monarch. 
despotism n. Any severe and strict rule in which the judgment of the governed has little or no part. 
destitute adj. Poverty-stricken. 
desultory adj. Not connected with what precedes. 
deter v. To frighten away. 
deteriorate v. To grow worse. 
determinate adj. Definitely limited or fixed. 
determination n. The act of deciding. 
deterrent adj. Hindering from action through fear. 
detest v. To dislike or hate with intensity. 
detract v. To take away in such manner as to lessen value or estimation. 
detriment n. Something that causes damage, depreciation, or loss. 
detrude v. To push down forcibly. 
deviate v. To take a different course. 
devilry n. Malicious mischief. 
deviltry n. Wanton and malicious mischief. 
devious adj. Out of the common or regular track. 
devise v. To invent. 
devout adj. Religious. 
dexterity n. Readiness, precision, efficiency, and ease in any physical activity or in any mechanical work.
diabolic adj. Characteristic of the devil. 
diacritical adj. Marking a difference. 
diagnose v. To distinguish, as a disease, by its characteristic phenomena. 
diagnosis n. Determination of the distinctive nature of a disease. 
dialect n. Forms of speech collectively that are peculiar to the people of a particular district. 
dialectician n. A logician. 
dialogue n. A formal conversation in which two or more take part. 
diaphanous adj. Transparent. 
diatomic adj. Containing only two atoms. 
diatribe n. A bitter or malicious criticism. 
dictum n. A positive utterance. 
didactic adj. Pertaining to teaching. 
difference n. Dissimilarity in any respect. 
differentia n. Any essential characteristic of a species by reason of which it differs from other species. 
differential adj. Distinctive. 
differentiate v. To acquire a distinct and separate character. 
diffidence n. Self-distrust. 
diffident adj. Affected or possessed with self-distrust. 
diffusible adj. Spreading rapidly through the system and acting quickly. 
diffusion n. Dispersion. 
dignitary n. One who holds high rank. 
digraph n. A union of two characters representing a single sound. 
digress v. To turn aside from the main subject and for a time dwell on some incidental matter. 
dilapidated pa. Fallen into decay or partial ruin. 
dilate v. To enlarge in all directions. 
dilatory adj. Tending to cause delay. 
dilemma n. A situation in which a choice between opposing modes of conduct is necessary. 
dilettante n. A superficial amateur. 
diligence n. Careful and persevering effort to accomplish what is undertaken. 
dilute v. To make more fluid or less concentrated by admixture with something. 
diminution n. Reduction. 
dimly adv. Obscurely. 
diphthong n. The sound produced by combining two vowels in to a single syllable or running together the sounds. 
diplomacy n. Tact, shrewdness, or skill in conducting any kind of negotiations or in social matters. 
diplomat n. A representative of one sovereign state at the capital or court of another. 
diplomatic adj. Characterized by special tact in negotiations. 
diplomatist n. One remarkable for tact and shrewd management. 
disagree v. To be opposite in opinion. 
disallow v. To withhold permission or sanction. 
disappear v. To cease to exist, either actually or for the time being. 
disappoint v. To fail to fulfill the expectation, hope, wish, or desire of. 
disapprove v. To regard with blame. 
disarm v. To deprive of weapons. 
disarrange v. To throw out of order. 
disavow v. To disclaim responsibility for. 
disavowal n. Denial. 
disbeliever n. One who refuses to believe. 
disburden v. To disencumber. 
disburse v. To pay out or expend, as money from a fund. 
discard v. To reject. 
discernible adj. Perceivable. 
disciple n. One who believes the teaching of another, or who adopts and follows some doctrine. 
disciplinary adj. Having the nature of systematic training or subjection to authority. 
discipline v. To train to obedience. 
disclaim v. To disavow any claim to, connection with, or responsibility to. 
discolor v. To stain. 
discomfit v. To put to confusion. 
discomfort n. The state of being positively uncomfortable. 
disconnect v. To undo or dissolve the connection or association of. 
disconsolate adj. Grief-stricken. 
discontinuance n. Interruption or intermission. 
discord n. Absence of harmoniousness. 
discountenance v. To look upon with disfavor. 
discover v. To get first sight or knowledge of, as something previously unknown or unperceived. 
discredit v. To injure the reputation of. 
discreet adj. Judicious. 
discrepant adj. Opposite. 
discriminate v. To draw a distinction. 
discursive adj. Passing from one subject to another. 
discussion n. Debate. 
disenfranchise v. To deprive of any right privilege or power 
disengage v. To become detached. 
disfavor n. Disregard. 
disfigure v. To impair or injure the beauty, symmetry, or appearance of. 
dishabille n. Undress or negligent attire. 
dishonest adj. Untrustworthy. 
disillusion v. To disenchant. 
disinfect v. To remove or destroy the poison of infectious or contagious diseases. 
disinfectant n. A substance used to destroy the germs of infectious diseases. 
disinherit v. To deprive of an inheritance. 
disinterested adj. Impartial. 
disjunctive adj. Helping or serving to disconnect or separate. 
dislocate v. To put out of proper place or order. 
dismissal n. Displacement by authority from an office or an employment. 
dismount v. To throw down, push off, or otherwise remove from a horse or the like. 
disobedience n. Neglect or refusal to comply with an authoritative injunction. 
disobedient adj. Neglecting or refusing to obey. 
disown v. To refuse to acknowledge as one’s own or as connected with oneself. 
disparage v. To regard or speak of slightingly. 
disparity n. Inequality. 
dispel v. To drive away by or as by scattering in different directions. 
dispensation n. That which is bestowed on or appointed to one from a higher power. 
displace v. To put out of the proper or accustomed place. 
dispossess v. To deprive of actual occupancy, especially of real estate. 
disputation n. Verbal controversy. 
disqualify v. To debar. 
disquiet v. To deprive of peace or tranquillity.
disregard v. To take no notice of. 
disreputable adj. Dishonorable or disgraceful. 
disrepute n. A bad name or character. 
disrobe v. To unclothe. 
disrupt v. To burst or break asunder. 
dissatisfy v. To displease. 
dissect v. To cut apart or to pieces. 
dissection n. The act or operation of cutting in pieces, specifically of a plant or an animal. 
dissemble v. To hide by pretending something different. 
disseminate v. To sow or scatter abroad, as seed is sown. 
dissension n. Angry or violent difference of opinion. 
dissent n. Disagreement. 
dissentient n. One who disagrees. 
dissentious adj. Contentious. 
dissertation n. Thesis. 
disservice n. An ill turn. 
dissever v. To divide. 
dissimilar adj. Different. 
dissipate v. To disperse or disappear. 
dissipation n. The state of being dispersed or scattered. 
dissolute adj. Lewd. 
dissolution n. A breaking up of a union of persons. 
dissolve v. To liquefy or soften, as by heat or moisture. 
dissonance n. Discord. 
dissonant adj. Harsh or disagreeable in sound. 
dissuade v. To change the purpose or alter the plans of by persuasion, counsel, or pleading. 
dissuasion n. The act of changing the purpose of or altering the plans of through persuasion, or pleading. 
disyllable n. A word of two syllables. 
distemper n. A disease or malady. 
distend v. To stretch out or expand in every direction. 
distensible adj. Capable of being stretched out or expanded in every direction. 
distention n. Expansion. 
distill v. To extract or produce by vaporization and condensation. 
distillation n. Separation of the more volatile parts of a substance from those less volatile. 
distiller n. One occupied in the business of distilling alcoholic liquors. 
distinction n. A note or designation of honor, officially recognizing superiority or success in studies. 
distort v. To twist into an unnatural or irregular form. 
distrain v. To subject a person to distress. 
distrainor n. One who subjects a person to distress. 
distraught adj. Bewildered. 
distrust n. Lack of confidence in the power, wisdom, or good intent of any person. 
disunion n. Separation of relations or interests. 
diurnal adj. Daily. 
divagation n. Digression. 
divergent adj. Tending in different directions. 
diverse adj. Capable of various forms. 
diversion n. Pastime. 
diversity n. Dissimilitude. 
divert v. To turn from the accustomed course or a line of action already established. 
divertible adj. Able to be turned from the accustomed course or a line of action already established. 
divest v. To strip, specifically of clothes, ornaments, or accouterments or disinvestment. 
divination n. The pretended forecast of future events or discovery of what is lost or hidden. 
divinity n. The quality or character of being godlike. 
divisible adj. Capable of being separated into parts. 
divisor n. That by which a number or quantity is divided. 
divulge v. To tell or make known, as something previously private or secret. 
divulgence n. A divulging. 
docile adj. Easy to manage. 
docket n. The registry of judgments of a court. 
doe n. The female of the deer. 
dogma n. A statement of religious faith or duty formulated by a body claiming authority. 
dogmatic adj. Making statements without argument or evidence. 
dogmatize v. To make positive assertions without supporting them by argument or evidence. 
doleful adj. Melancholy. 
dolesome adj. Melancholy. 
dolor n. Lamentation. 
dolorous adj. Expressing or causing sorrow or pain. 
domain n. A sphere or field of action or interest. 
domesticity n. Life in or fondness for one’s home and family. 
domicile n. The place where one lives. 
dominance n. Ascendancy. 
dominant adj. Conspicuously prominent. 
dominate v. To influence controllingly. 
domination n. Control by the exercise of power or constituted authority. 
domineer v. To rule with insolence or unnecessary annoyance. 
donate v. To bestow as a gift, especially for a worthy cause. 
donator n. One who makes a donation or present. 
donee n. A person to whom a donation is made. 
donor n. One who makes a donation or present. 
dormant adj. Being in a state of or resembling sleep. 
doublet n. One of a pair of like things. 
doubly adv. In twofold degree or extent. 
dowry n. The property which a wife brings to her husband in marriage. 
drachma n. A modern and an ancient Greek coin. 
dragnet n. A net to be drawn along the bottom of the water. 
dragoon n. In the British army, a cavalryman. 
drainage n. The means of draining collectively, as a system of conduits, trenches, pipes, etc. 
dramatist n. One who writes plays. 
dramatize v. To relate or represent in a dramatic or theatrical manner. 
drastic adj. Acting vigorously. 
drought n. Dry weather, especially when so long continued as to cause vegetation to wither. 
drowsy adj. Heavy with sleepiness. 
drudgery n. Hard and constant work in any menial or dull occupation. 
dubious adj. Doubtful. 
duckling n. A young duck. 
ductile adj. Capable of being drawn out, as into wire or a thread. 
duet n. A composition for two voices or instruments. 
dun v. To make a demand or repeated demands on for payment. 
duplex adj. Having two parts. 
duplicity n. Double-dealing. 
durance n. Confinement. 
duration n. The period of time during which anything lasts. 
duteous adj. Showing submission to natural superiors. 
dutiable adj. Subject to a duty, especially a customs duty. 
dutiful adj. Obedient. 
dwindle v. To diminish or become less. 
dyne n. The force which, applied to a mass of one gram for 1 second, would give it a velocity of 1 cm/s. 
earnest adj. Ardent in spirit and speech. 
earthenware n. Anything made of clay and baked in a kiln or dried in the sun. 
eatable adj. Edible. 
ebullient adj. Showing enthusiasm or exhilaration of feeling. 
eccentric adj. Peculiar. 
eccentricity n. Idiosyncrasy. 
eclipse n. The obstruction of a heavenly body by its entering into the shadow of another body. 
economize v. To spend sparingly. 
ecstasy n. Rapturous excitement or exaltation. 
ecstatic adj. Enraptured. 
edible adj. Suitable to be eaten. 
edict n. That which is uttered or proclaimed by authority as a rule of action. 
edify v. To build up, or strengthen, especially in morals or religion. 
editorial n. An article in a periodical written by the editor and published as an official argument. 
educe v. To draw out. 
efface v. To obliterate. 
effect n. A consequence. 
effective adj. Fit for a destined purpose. 
effectual adj. Efficient. 
effeminacy n. Womanishness. 
effeminate adj. Having womanish traits or qualities. 
effervesce v. To bubble up. 
effervescent adj. Giving off bubbles of gas. 
effete adj. Exhausted, as having performed its functions. 
efficacious adj. Effective. 
efficacy n. The power to produce an intended effect as shown in the production of it. 
efficiency n. The state of possessing adequate skill or knowledge for the performance of a duty. 
efficient adj. Having and exercising the power to produce effects or results. 
efflorescence n. The state of being flowery, or a flowery appearance. 
efflorescent adj. Opening in flower. 
effluvium n. A noxious or ill-smelling exhalation from decaying or putrefying matter. 
effrontery n. Unblushing impudence. 
effulgence n. Splendor. 
effuse v. To pour forth. 
effusion n. an outpouring. 
egoism n. The theory that places man’s chief good in the completeness of self. 
egoist n. One who advocates or practices egoism. 
egotism n. Self-conceit. 
egotist n. One given to self-mention or who is constantly telling of his own views and experiences. 
egregious adj. Extreme. 
egress n. Any place of exit. 
eject v. To expel. 
elapse v. To quietly terminate: said of time. 
elasticity n. That property of matter by which a body tends to return to a former shape after being changed. 
electrolysis n. The process of decomposing a chemical compound by the passage of an electric current. 
electrotype n. A metallic copy of any surface, as a coin. 
elegy n. A lyric poem lamenting the dead. 
element n. A component or essential part. 
elicit v. To educe or extract gradually or without violence. 
eligible adj. Qualified for selection. 
eliminate v. To separate and cast aside. 
Elizabethan adj. Relating to Elizabeth, queen of England, or to her era. 
elocution n. The art of correct intonation, inflection, and gesture in public speaking or reading. 
eloquent adj. Having the ability to express emotion or feeling in lofty and impassioned speech. 
elucidate v. To bring out more clearly the facts concerning. 
elude v. To evade the search or pursuit of by dexterity or artifice. 
elusion n. Evasion. 
emaciate v. To waste away in flesh. 
emanate v. To flow forth or proceed, as from some source. 
emancipate v. To release from bondage. 
embargo n. Authoritative stoppage of foreign commerce or of any special trade. 
embark v. To make a beginning in some occupation or scheme. 
embarrass v. To render flustered or agitated. 
embellish v. To make beautiful or elegant by adding attractive or ornamental features. 
embezzle v. To misappropriate secretly. 
emblazon v. To set forth publicly or in glowing terms. 
emblem n. A symbol. 
embody v. To express, formulate, or exemplify in a concrete, compact or visible form. 
embolden v. To give courage to. 
embolism n. An obstruction or plugging up of an artery or other blood-vessel. 
embroil v. To involve in dissension or strife. 
emerge v. To come into view or into existence. 
emergence n. A coming into view. 
emergent adj. Coming into view. 
emeritus adj. Retired from active service but retained to an honorary position. 
emigrant n. One who moves from one place to settle in another. 
emigrate v. To go from one country, state, or region for the purpose of settling or residing in another. 
eminence n. An elevated position with respect to rank, place, character, condition, etc. 
eminent adj. High in station, merit, or esteem. 
emit v. To send or give out. 
emphasis n. Any special impressiveness added to an utterance or act, or stress laid upon some word. 
emphasize v. To articulate or enunciate with special impressiveness upon a word, or a group of words. 
emphatic adj. Spoken with any special impressiveness laid upon an act, word, or set of words. 
employee n. One who works for wages or a salary. 
employer n. One who uses or engages the services of other persons for pay. 
emporium n. A bazaar or shop. 
empower v. To delegate authority to. 
emulate v. To imitate with intent to equal or surpass. 
enact v. To make into law, as by legislative act. 
enamor v. To inspire with ardent love. 
encamp v. To pitch tents for a resting-place. 
encomium n. A formal or discriminating expression of praise. 
encompass v. To encircle. 
encore n. The call for a repetition, as of some part of a play or performance. 
encourage v. To inspire with courage, hope, or strength of mind. 
encroach v. To invade partially or insidiously and appropriate the possessions of another. 
encumber v. To impede with obstacles. 
encyclical adj. Intended for general circulation. 
encyclopedia n. A work containing information on subjects, or exhaustive of one subject. 
endanger v. To expose to peril. 
endear v. To cause to be loved. 
endemic adj. Peculiar to some specified country or people. 
endue v. To endow with some quality, gift, or grace, usually spiritual. 
endurable adj. Tolerable. 
endurance n. The ability to suffer pain, distress, hardship, or stress of any kind without succumbing. 
energetic adj. Working vigorously. 
enervate v. To render ineffective or inoperative. 
enfeeble v. To debilitate. 
enfranchise v. To endow with a privilege, especially with the right to vote. 
engender v. To produce. 
engrave v. To cut or carve in or upon some surface. 
engross v. To occupy completely. 
enhance v. To intensify. 
enigma n. A riddle. 
enjoin v. To command. 
enkindle v. To set on fire. 
enlighten v. To cause to see clearly. 
enlist v. To enter voluntarily the military service by formal enrollment. 
enmity n. Hatred. 
ennoble v. To dignify. 
enormity n. Immensity. 
enormous adj. Gigantic. 
enrage v. To infuriate. 
enrapture v. To delight extravagantly or intensely. 
enshrine v. To keep sacred. 
ensnare v. To entrap. 
entail v. To involve; necessitate. 
entangle v. To involve in difficulties, confusion, or complications. 
enthrall v. To bring or hold under any overmastering influence. 
enthrone v. To invest with sovereign power. 
enthuse v. To yield to or display intense and rapturous feeling. 
enthusiastic adj. Full of zeal and fervor. 
entirety n. A complete thing. 
entomology n. The branch of zoology that treats of insects. 
entrails n. pl. The internal parts of an animal. 
entreaty n. An earnest request. 
entree n. The act of entering. 
entrench v. To fortify or protect, as with a trench or ditch and wall. 
entwine v. To interweave. 
enumerate v. To name one by one. 
epic n. A poem celebrating in formal verse the mythical achievements of great personages, heroes, etc. 
epicure n. One who cultivates a delicate taste for eating and drinking. 
Epicurean adj. Indulging, ministering, or pertaining to daintiness of appetite. 
epicycle n. A circle that rolls upon the external or internal circumference of another circle. 
epicycloid n. A curve traced by a point on the circumference of a circle which rolls upon another circle. 
epidemic n. Wide-spread occurrence of a disease in a certain region. 
epidermis n. The outer skin. 
epigram n. A pithy phrasing of a shrewd observation. 
epilogue n. The close of a narrative or dramatic poem. 
epiphany n. Any appearance or bodily manifestation of a deity. 
episode n. An incident or story in a literary work, separable from yet growing out of it. 
epitaph n. An inscription on a tomb or monument in honor or in memory of the dead. 
epithet n. Word used adjectivally to describe some quality or attribute of is objects, as in “Father Aeneas”.
epitome n. A simplified representation. 
epizootic adj. Prevailing among animals. 
epoch n. A interval of time, memorable for extraordinary events. 
epode n. A species of lyric poems. 
equalize v. To render uniform. 
equanimity n. Evenness of mind or temper. 
equestrian adj. Pertaining to horses or horsemanship. 
equilibrium n. A state of balance. 
equitable adj. Characterized by fairness. 
equity n. Fairness or impartiality. 
equivalent adj. Equal in value, force, meaning, or the like. 
equivocal adj. Ambiguous. 
equivocate v. To use words of double meaning. 
eradicate v. To destroy thoroughly. 
errant adj. Roving or wandering, as in search of adventure or opportunity for gallant deeds. 
erratic adj. Irregular. 
erroneous adj. Incorrect. 
erudite adj. Very-learned. 
erudition n. Extensive knowledge of literature, history, language, etc. 
eschew v. To keep clear of. 
espy v. To keep close watch. 
esquire n. A title of dignity, office, or courtesy. 
essence n. That which makes a thing to be what it is. 
esthetic adj. Pertaining to beauty, taste, or the fine arts. 
estimable adj. Worthy of respect. 
estrange v. To alienate. 
estuary n. A wide lower part of a tidal river. 
et cetera Latin. And so forth. 
eugenic adj. Relating to the development and improvement of race. 
eulogize v. To speak or write a laudation of a person’s life or character. 
eulogy n. A spoken or written laudation of a person’s life or character. 
euphemism n. A figure of speech by which a phrase less offensive is substituted. 
euphonious adj. Characterized by agreeableness of sound. 
euphony n. Agreeableness of sound. 
eureka Greek. I have found it. 
evade v. To avoid by artifice. 
evanesce v. To vanish gradually. 
evanescent adj. Fleeting. 
evangelical adj. Seeking the conversion of sinners. 
evangelist n. A preacher who goes from place to place holding services. 
evasion n. Escape. 
eventual adj. Ultimate. 
evert v. To turn inside out. 
evict v. To dispossess pursuant to judicial decree. 
evidential adj. Indicative. 
evince v. To make manifest or evident. 
evoke v. To call or summon forth. 
evolution n. Development or growth. 
evolve v. To unfold or expand. 
exacerbate v. To make more sharp, severe, or virulent. 
exaggerate v. To overstate. 
exasperate v. To excite great anger in. 
excavate v. To remove by digging or scooping out. 
exceed v. To go beyond, as in measure, quality, value, action, power, skill, etc. 
excel v. To be superior or distinguished. 
excellence n. Possession of eminently or unusually good qualities. 
excellency n. A title of honor bestowed upon various high officials. 
excellent adj. Possessing distinguished merit. 
excerpt n. An extract or selection from written or printed matter. 
excess n. That which passes the ordinary, proper, or required limit, measure, or experience. 
excitable adj. Nervously high-strung. 
excitation n. Intensified emotion or action. 
exclamation n. An abrupt or emphatic expression of thought or of feeling. 
exclude v. To shut out purposely or forcibly. 
exclusion n. Non-admission. 
excrescence n. Any unnatural addition, outgrowth, or development. 
excretion n. The getting rid of waste matter. 
excruciate v. To inflict severe pain or agony upon. 
excursion n. A journey. 
excusable adj. Justifiable. 
execrable adj. Abominable. 
execration n. An accursed thing. 
executor n. A person nominated by the will of another to execute the will. 
exegesis n. Biblical exposition or interpretation. 
exemplar n. A model, pattern, or original to be copied or imitated. 
exemplary adj. Fitted to serve as a model or example worthy of imitation. 
exemplify v. To show by example. 
exempt adj. Free, clear, or released, as from some liability, or restriction affecting others. 
exert v. To make an effort. 
exhale v. To breathe forth. 
exhaust v. To empty by draining off the contents. 
exhaustible adj. Causing or tending to cause exhaustion. 
exhaustion n. Deprivation of strength or energy. 
exhaustive adj. Thorough and complete in execution. 
exhilarate v. To fill with high or cheerful spirits. 
exhume v. To dig out of the earth (what has been buried). 
exigency n. A critical period or condition. 
exigent adj. Urgent. 
existence n. Possession or continuance of being. 
exit n. A way or passage out. 
exodus n. A going forth or departure from a place or country, especially of many people. 
exonerate v. To relieve or vindicate from accusation, imputation, or blame. 
exorbitance n. Extravagance or enormity. 
exorbitant adj. Going beyond usual and proper limits. 
exorcise v. To cast or drive out by religious or magical means. 
exotic adj. Foreign. 
expand v. To increase in range or scope. 
expanse n. A continuous area or stretch. 
expansion n. Increase of amount, size, scope, or the like. 
expatriate v. To drive from one’s own country. 
expect v. To look forward to as certain or probable. 
expectancy n. The act or state of looking forward to as certain or probable. 
expectorate v. To cough up and spit forth. 
expediency n. Fitness to meet the requirements of a particular case. 
expedient adj. Contributing to personal advantage. 
expedite v. To hasten the movement or progress of. 
expeditious adj. Speedy. 
expend v. To spend. 
expense n. The laying out or expending or money or other resources, as time or strength. 
expiate v. To make satisfaction or amends for. 
explicate v. To clear from involvement. 
explicit adj. Definite. 
explode v. To cause to burst in pieces by force from within. 
explosion n. A sudden and violent outbreak. 
explosive adj. Pertaining to a sudden and violent outbreak. 
exposition n. Formal presentation. 
expository adj. Pertaining to a formal presentation. 
expostulate v. To discuss. 
exposure n. An open situation or position in relation to the sun, elements, or points of the compass. 
expressive adj. Full of meaning. 
expulsion n. Forcible ejection. 
extant adj. Still existing and known. 
extemporaneous adj. Done or made without much or any preparation. 
extempore adv. Without studied or special preparation. 
extensible adj. Capable of being thrust out. 
extension n. A reaching or stretching out, as in space, time or scope. 
extensive adj. Extended widely in space, time, or scope. 
extensor n. A muscle that causes extension. 
extenuate v. To diminish the gravity or importance of. 
exterior n. That which is outside. 
external n. Anything relating or belonging to the outside. 
extinct adj. Being no longer in existence. 
extinguish v. To render extinct. 
extol v. To praise in the highest terms. 
extort v. To obtain by violence, threats, compulsion, or the subjection of another to some necessity. 
extortion n. The practice of obtaining by violence or compulsion. 
extradite v. To surrender the custody of. 
extradition n. The surrender by a government of a person accused of crime to the justice of another government. 
extrajudicial adj. Happening out of court. 
extraneous adj. Having no essential relation to a subject. 
extraordinary adj. Unusual. 
extravagance n. Undue expenditure of money. 
extravagant adj. Needlessly free or lavish in expenditure. 
extremist n. One who supports extreme measures or holds extreme views. 
extremity n. The utmost point, side, or border, or that farthest removed from a mean position. 
extricate v. Disentangle. 
extrude v. To drive out or away. 
exuberance n. Rich supply. 
exuberant adj. Marked by great plentifulness. 
fabricate v. To invent fancifully or falsely. 
fabulous adj. Incredible. 
facet n. One of the small triangular plane surfaces of a diamond or other gem. 
facetious adj. Amusing. 
facial adj. Pertaining to the face. 
facile adj. Not difficult to do. 
facilitate v. To make more easy. 
facility n. Ease. 
facsimile n. An exact copy or reproduction. 
faction n. A number of persons combined for a common purpose. 
factious adj. Turbulent. 
fallacious adj. Illogical. 
fallacy n. Any unsound or delusive mode of reasoning, or anything based on such reasoning. 
fallible adj. Capable of erring. 
fallow n. Land broken up and left to become mellow or to rest. 
famish v. To suffer extremity of hunger or thirst. 
fanatic n. A religious zealot. 
fancier n. One having a taste for or interest in special objects. 
fanciless adj. Unimaginative. 
fastidious adj. Hard to please. 
fathom n. A measure of length, 6 feet. 
fatuous adj. Idiotic 
faulty adj. Imperfect. 
faun n. One of a class of deities of the woods and herds represented as half human, with goats feet. 
fawn n. A young deer. 
fealty n. Loyalty. 
feasible adj. That may be done, performed, or effected; practicable. 
federate v. To league together. 
feint n. Any sham, pretense, or deceptive movement. 
felicitate v. To wish joy or happiness to, especially in view of a coming event. 
felicity n. A state of well-founded happiness. 
felon n. A criminal or depraved person. 
felonious adj. Showing criminal or evil purpose. 
felony n. One of the highest class of offenses, and punishable with death or imprisonment. 
feminine adj. Characteristic of woman or womankind. 
fernery n. A place in which ferns are grown. 
ferocious adj. Of a wild, fierce, and savage nature. 
ferocity n. Savageness. 
fervent adj. Ardent in feeling. 
fervid adj. Intense. 
fervor n. Ardor or intensity of feeling. 
festal adj. Joyous. 
festive adj. Merry. 
fete n. A festival or feast. 
fetus n. The young in the womb or in the egg. 
feudal adj. Pertaining to the relation of lord and vassal. 
feudalism n. The feudal system. 
fez n. A brimless felt cap in the shape of a truncated cone, usually red with a black tassel. 
fiasco n. A complete or humiliating failure. 
fickle adj. Unduly changeable in feeling, judgment, or purpose. 
fictitious adj. Created or formed by the imagination. 
fidelity n. Loyalty. 
fiducial adj. Indicative of faith or trust. 
fief n. A landed estate held under feudal tenure. 
filibuster n. One who attempts to obstruct legislation. 
finale n. Concluding performance. 
finality n. The state or quality of being final or complete. 
finally adv. At last. 
financial adj. Monetary. 
financier n. One skilled in or occupied with financial affairs or operations. 
finery n. That which is used to decorate the person or dress. 
finesse n. Subtle contrivance used to gain a point. 
finite adj. Limited. 
fiscal adj. Pertaining to the treasury or public finances of a government. 
fishmonger n. One who sells fish. 
fissure n. A crack or crack-like depression. 
fitful adj. Spasmodic. 
fixture n. One who or that which is expected to remain permanently in its position. 
flag-officer n. The captain of a flag-ship. 
flagrant adj. Openly scandalous. 
flamboyant adj. Characterized by extravagance and in general by want of good taste. 
flatulence n. Accumulation of gas in the stomach and bowels. 
flection n. The act of bending. 
fledgling n. A young bird. 
flexible adj. Pliable. 
flimsy adj. Thin and weak. 
flippant adj. Having a light, pert, trifling disposition. 
floe n. A collection of tabular masses of floating polar ice. 
flora n. The aggregate of plants growing without cultivation in a district. 
floral adj. Pertaining to flowers. 
florid adj. Flushed with red. 
florist n. A dealer in flowers. 
fluctuate v. To pass backward and forward irregularly from one state or degree to another. 
fluctuation n. Frequent irregular change back and forth from one state or degree to another. 
flue n. A smoke-duct in a chimney. 
fluent adj. Having a ready or easy flow of words or ideas. 
fluential adj. Pertaining to streams. 
flux n. A state of constant movement, change, or renewal. 
foggy adj. Obscure. 
foible n. A personal weakness or failing. 
foist v. To palm off. 
foliage n. Any growth of leaves. 
folio n. A sheet of paper folded once, or of a size adapted to folding once. 
folk-lore n. The traditions, beliefs, and customs of the common people. 
fondle v. To handle tenderly and lovingly. 
foolery n. Folly. 
foot-note n. A note of explanation or comment at the foot of a page or column. 
foppery n. Dandyism. 
foppish adj. Characteristic of one who is unduly devoted to dress and the niceties of manners. 
forbearance n. Patient endurance or toleration of offenses. 
forby adv. Besides. 
forcible adj. Violent. 
forecourt n. A court opening directly from the street. 
forejudge v. To judge of before hearing evidence. 
forepeak n. The extreme forward part of a ship’s hold, under the lowest deck. 
foreshore n. That part of a shore uncovered at low tide. 
forebode v. To be an omen or warning sign of, especially of evil. 
forecast v. To predict. 
forecastle n. That part of the upper deck of a ship forward of the after fore-shrouds. 
foreclose v. To bar by judicial proceedings the equitable right of a mortgagor to redeem property. 
forefather n. An ancestor. 
forego v. To deny oneself the pleasure or profit of. 
foreground n. That part of a landscape or picture situated or represented as nearest the spectator. 
forehead n. The upper part of the face, between the eyes and the hair. 
foreign adj. Belonging to, situated in, or derived from another country. 
foreigner n. A citizen of a foreign country. 
foreknowledge n. Prescience. 
foreman n. The head man. 
foreordain v. To predetermine. 
foreordination n. Predestination. 
forerun v. To go before as introducing or ushering in. 
foresail n. A square sail. 
foresee v. To discern beforehand. 
foresight n. Provision against harm or need. 
foretell v. To predict. 
forethought n. Premeditation. 
forfeit v. To lose possession of through failure to fulfill some obligation. 
forfend v. To ward off. 
forgery n. Counterfeiting. 
forgo v. To deny oneself. 
formation n. Relative disposition of parts. 
formidable adj. Difficult to accomplish. 
formula n. Fixed rule or set form. 
forswear v. To renounce upon oath. 
forte n. A strong point. 
forth adv. Into notice or view. 
forthright adv. With directness. 
fortify v. To provide with defensive works. 
fortitude n. Patient courage. 
foursome adj. Consisting of four. 
fracture n. A break. 
fragile adj. Easily broken. 
frailty n. Liability to be broken or destroyed. 
fragile adj. Capable of being broken. 
frankincense n. A gum or resin which on burning yields aromatic fumes. 
frantic adj. Frenzied. 
fraternal adj. Brotherly. 
fraudulence n. Deceitfulness. 
fraudulent adj. Counterfeit. 
fray v. To fret at the edge so as to loosen or break the threads. 
freemason n. A member of an ancient secret fraternity originally confined to skilled artisans. 
freethinker n. One who rejects authority or inspiration in religion. 
free trade n. Commerce unrestricted by tariff or customs. 
frequency n. The comparative number of any kind of occurrences within a given time or space. 
fresco n. The art of painting on a surface of plaster, particularly on walls and ceilings. 
freshness n. The state, quality, or degree of being fresh. 
fretful adj. Disposed to peevishness. 
frightful adj. Apt to induce terror or alarm. 
frigid adj. Lacking warmth. 
frigidarium n. A room kept at a low temperature for preserving fruits, meat, etc. 
frivolity n. A trifling act, thought, saying, or practice. 
frivolous adj. Trivial. 
frizz v. To give a crinkled, fluffy appearance to. 
frizzle v. To cause to crinkle or curl, as the hair. 
frolicsome adj. Prankish. 
frontier n. The part of a nation’s territory that abuts upon another country. 
frowzy adj. Slovenly in appearance. 
frugal adj. Economical. 
fruition n. Fulfillment. 
fugacious adj. Fleeting. 
fulcrum n. The support on or against which a lever rests, or the point about which it turns. 
fulminate v. To cause to explode. 
fulsome adj. Offensive from excess of praise or commendation. 
fumigate v. To subject to the action of smoke or fumes, especially for disinfection. 
functionary n. An official. 
fundamental adj. Basal. 
fungible adj. That may be measured, counted, or weighed. 
fungous adj. Spongy. 
fungus n. A plant destitute of chlorophyll, as a mushroom. 
furbish v. To restore brightness or beauty to. 
furlong n. A measure, one-eighth of a mile. 
furlough n. A temporary absence of a soldier or sailor by permission of the commanding officer. 
furrier n. A dealer in or maker of fur goods. 
further adj. More distant or advanced. 
furtherance n. Advancement. 
furtive adj. Stealthy or sly, like the actions of a thief. 
fuse v. To unite or blend as by melting together. 
fusible adj. Capable of being melted by heat. 
futile adj. Of no avail or effect. 
futurist n. A person of expectant temperament. 
gauge n. An instrument for measuring. 
gaiety n. Festivity. 
gaily adv. Merrily. 
gait n. Carriage of the body in going. 
gallant adj. Possessing a brave or chivalrous spirit. 
galore adj. Abundant. 
galvanic adj. Pertaining or relating to electricity produced by chemical action. 
galvanism n. Current electricity, especially that arising from chemical action. 
galvanize v. To imbue with life or animation. 
gamble v. To risk money or other possession on an event, chance, or contingency. 
gambol n. Playful leaping or frisking. 
gamester n. A gambler. 
gamut n. The whole range or sequence. 
garnish v. In cookery, to surround with additions for embellishment. 
garrison n. The military force stationed in a fort, town, or other place for its defense. 
garrote v. To execute by strangling. 
garrulous adj. Given to constant trivial talking. 
gaseous adj. Light and unsubstantial. 
gastric adj. Of, pertaining to, or near the stomach. 
gastritis n. Inflammation of the stomach. 
gastronomy n. The art of preparing and serving appetizing food. 
gendarme n. In continental Europe, particularly in France, a uniformed and armed police officer. 
genealogy n. A list, in the order of succession, of ancestors and their descendants. 
genealogist n. A tracer of pedigrees. 
generality n. The principal portion. 
generalize v. To draw general inferences. 
generally adv. Ordinarily. 
generate v. To produce or cause to be. 
generic adj. Noting a genus or kind; opposed to specific. 
generosity n. A disposition to give liberally or to bestow favors heartily. 
genesis n. Creation. 
geniality n. Warmth and kindliness of disposition. 
genital adj. Of or pertaining to the animal reproductive organs. 
genitive adj. Indicating source, origin, possession, or the like. 
genteel adj. Well-bred or refined. 
gentile adj. Belonging to a people not Jewish. 
geology n. The department of natural science that treats of the constitution and structure of the earth. 
germane adj. Relevant. 
germinate v. To begin to develop into an embryo or higher form. 
gestation n. Pregnancy. 
gesticulate v. To make gestures or motions, as in speaking, or in place of speech. 
gesture n. A movement or action of the hands or face, expressive of some idea or emotion. 
ghastly adj. Hideous. 
gibe v. To utter taunts or reproaches. 
giddy adj. Affected with a whirling or swimming sensation in the head. 
gigantic adj. Tremendous. 
giver n. One who gives, in any sense. 
glacial adj. Icy, or icily cold. 
glacier n. A field or stream of ice. 
gladden v. To make joyous. 
glazier n. One who cuts and fits panes of glass, as for windows. 
glimmer n. A faint, wavering, unsteady light. 
glimpse n. A momentary look. 
globose adj. Spherical. 
globular adj. Spherical. 
glorious adj. Of excellence and splendor. 
glutinous adj. Sticky. 
gluttonous adj. Given to excess in eating. 
gnash v. To grind or strike the teeth together, as from rage. 
Gordian knot n. Any difficulty the only issue out of which is by bold or unusual manners. 
gourmand n. A connoisseur in the delicacies of the table. 
gosling n. A young goose. 
gossamer adj. Flimsy. 
gourd n. A melon, pumpkin, squash, or some similar fruit having a hard rind. 
graceless adj. Ungracious. 
gradation n. A step, degree, rank, or relative position in an order or series. 
gradient adj. Moving or advancing by steps. 
granary n. A storehouse for grain after it is thrashed or husked. 
grandeur n. The quality of being grand or admirably great. 
grandiloquent adj. Speaking in or characterized by a pompous or bombastic style. 
grandiose adj. Having an imposing style or effect. 
grantee n. The person to whom property is transferred by deed. 
grantor n. The maker of a deed. 
granular adj. Composed of small grains or particles. 
granulate v. To form into grains or small particles. 
granule n. A small grain or particle. 
grapple v. To take hold of. 
gratification n. Satisfaction. 
gratify v. To please, as by satisfying a physical or mental desire or need. 
gratuitous adj. Voluntarily. 
gratuity n. That which is given without demand or claim. Tip. 
gravity n. Seriousness. 
gregarious adj. Not habitually solitary or living alone. 
grenadier n. A member of a regiment composed of men of great stature. 
grief n. Sorrow. 
grievance n. That which oppresses, injures, or causes grief and at the same time a sense of wrong. 
grievous adj. Creating affliction. 
grimace n. A distortion of the features, occasioned by some feeling of pain, disgust, etc. 
grindstone n. A flat circular stone, used for sharpening tools. 
grisly adj. Fear-inspiring. 
grotesque adj. Incongruously composed or ill-proportioned. 
grotto n. A small cavern. 
ground n. A pavement or floor or any supporting surface on which one may walk. 
guess n. Surmise. 
guile n. Duplicity. 
guileless adj. Frank. 
guinea n. An English monetary unit. 
guise n. The external appearance as produced by garb or costume. 
gullible adj. Credulous. 
gumption n. Common sense. 
gusto n. Keen enjoyment. 
guy n. Stay-rope. 
guzzle v. To swallow greedily or hastily; gulp. 
gynecocracy n. Female supremacy. 
gynecology n. The science that treats of the functions and diseases peculiar to women. 
gyrate v. To revolve. 
gyroscope n. An instrument for illustrating the laws of rotation. 
habitable adj. Fit to be dwelt in. 
habitant n. Dweller. 
habitual adj. According to usual practice. 
habitude n. Customary relation or association. 
hackney v. To make stale or trite by repetition. 
haggard adj. Worn and gaunt in appearance. 
halcyon adj. Calm. 
hale adj. Of sound and vigorous health. 
handwriting n. Penmanship. 
hanger-on n. A parasite. 
happy-go-lucky adj. Improvident. 
harangue n. A tirade. 
harass v. To trouble with importunities, cares, or annoyances. 
harbinger n. One who or that which foreruns and announces the coming of any person or thing. 
hard-hearted adj. Lacking pity or sympathy. 
hardihood n. Foolish daring. 
harmonious adj. Concordant in sound. 
havoc n. Devastation. 
hawthorn n. A thorny shrub much used in England for hedges. 
hazard n. Risk. 
head first adv. Precipitately, as in diving. 
head foremost adv. Precipitately, as in diving. 
heartrending adj. Very depressing. 
heathenish adj. Irreligious. 
heedless adj. Thoughtless. 
heifer n. A young cow. 
heinous adj. Odiously sinful. 
hemorrhage n. Discharge of blood from a ruptured or wounded blood-vessel. 
hemorrhoids n. pl. Tumors composed of enlarged and thickened blood-vessels, at the lower end of the rectum. 
henchman n. A servile assistant and subordinate. 
henpeck v. To worry or harass by ill temper and petty annoyances. 
heptagon n. A figure having seven sides and seven angles. 
heptarchy n. A group of seven governments. 
herbaceous adj. Having the character of a herb. 
herbarium n. A collection of dried plants scientifically arranged for study. 
herbivorous adj. Feeding on herbs or other vegetable matter, as animals. 
hereditary adj. Passing naturally from parent to child. 
heredity n. Transmission of physical or mental qualities, diseases, etc., from parent to offspring. 
heresy n. An opinion or doctrine subversive of settled beliefs or accepted principles. 
heretic n. One who holds opinions contrary to the recognized standards or tenets of any philosophy. 
heritage n. Birthright. 
hernia n. Protrusion of any internal organ in whole or in part from its normal position. 
hesitancy n. A pausing to consider. 
hesitant adj. Vacillating. 
hesitation n. Vacillation. 
heterodox adj. At variance with any commonly accepted doctrine or opinion. 
heterogeneity n. Unlikeness of constituent parts. 
heterogeneous adj. Consisting of dissimilar elements or ingredients of different kinds. 
heteromorphic adj. Deviating from the normal form or standard type. 
hexangular adj. Having six angles. 
hexapod adj. Having six feet. 
hexagon n. A figure with six angles. 
hiatus n. A break or vacancy where something necessary to supply the connection is wanting. 
hibernal adj. Pertaining to winter. 
Hibernian adj. Pertaining to Ireland, or its people. 
hideous adj. Appalling. 
hilarious adj. Boisterously merry. 
hillock n. A small hill or mound. 
hinder v. To obstruct. 
hindmost adj. Farthest from the front. 
hindrance n. An obstacle. 
hirsute adj. Having a hairy covering. 
hoard v. To gather and store away for the sake of accumulation. 
hoarse adj. Having the voice harsh or rough, as from a cold or fatigue. 
homage n. Reverential regard or worship. 
homogeneity n. Congruity of the members or elements or parts. 
homogeneous adj. Made up of similar parts or elements. 
homologous adj. Identical in nature, make-up, or relation. 
homonym n. A word agreeing in sound with but different in meaning from another. 
homophone n. A word agreeing in sound with but different in meaning from another. 
honorarium n. A token fee or payment to a professional man for services. 
hoodwink v. To deceive. 
horde n. A gathered multitude of human beings. 
hosiery n. A stocking. 
hospitable adj. Disposed to treat strangers or guests with generous kindness. 
hospitality n. The practice of receiving and entertaining strangers and guests with kindness. 
hostility n. Enmity. 
huckster n. One who retails small wares. 
humane adj. Compassionate. 
humanitarian n. A philanthropist. 
humanize v. To make gentle or refined. 
humbug n. Anything intended or calculated to deceive or mislead. 
humiliate v. To put to shame. 
hussar n. A light-horse trooper armed with saber and carbine. 
hustle v. To move with haste and promptness. 
hybrid adj. Cross-bred. 
hydra n. The seven- or nine-headed water-serpent slain by Hercules. 
hydraulic adj. Involving the moving of water, of the force exerted by water in motion. 
hydrodynamics n. The branch of mechanics that treats of the dynamics of fluids. 
hydroelectric adj. Pertaining to electricity developed water or steam. 
hydromechanics n. The mechanics of fluids. 
hydrometer n. An instrument for determining the density of solids and liquids by flotation. 
hydrostatics n. The branch of science that treats of the pressure and equilibrium of fluids. 
hydrous adj. Watery. 
hygiene n. The branch of medical science that relates to improving health. 
hypercritical adj. Faultfinding. 
hypnosis n. An artificial trance-sleep. 
hypnotic adj. Tending to produce sleep. 
hypnotism n. An artificially induced somnambulistic state in which the mind readily acts on suggestion. 
hypnotize v. To produce a somnambulistic state in which the mind readily acts on suggestions. 
hypocrisy n. Extreme insincerity. 
hypocrite n. One who makes false professions of his views or beliefs. 
hypodermic adj. Pertaining to the area under the skin. 
hypotenuse n. The side of a right-angled triangle opposite the right angle. 
hypothesis n. A proposition taken for granted as a premise from which to reach a conclusion. 
hysteria n. A nervous affection occurring typically in paroxysms of laughing and crying. 
ichthyic adj. Fish-like. 
ichthyology n. The branch of zoology that treats of fishes. 
ichthyosaurs n. A fossil reptile. 
icily adv. Frigidly. 
iciness n. The state of being icy. 
icon n. An image or likeness. 
iconoclast n. An image-breaker. 
idealize v. To make to conform to some mental or imaginary standard. 
idiom n. A use of words peculiar to a particular language. 
idiosyncrasy n. A mental quality or habit peculiar to an individual. 
idolize v. To regard with inordinate love or admiration. 
ignoble adj. Low in character or purpose. 
ignominious adj. Shameful. 
Iliad n. A Greek epic poem describing scenes from the siege of Troy. 
illegal adj. Not according to law. 
illegible adj. Undecipherable. 
illegitimate adj. Unlawfully begotten. 
illiberal adj. Stingy. 
illicit adj. Unlawful. 
illimitable adj. Boundless. 
illiterate adj. Having little or no book-learning. 
ill-natured adj. Surly. 
illogical adj. Contrary to the rules of sound thought. 
illuminant n. That which may be used to produce light. 
illuminate v. To supply with light. 
illumine v. To make bright or clear. 
illusion n. An unreal image presented to the senses. 
illusive adj. Deceptive. 
illusory adj. Deceiving or tending to deceive, as by false appearance. 
imaginable adj. That can be imagined or conceived in the mind. 
imaginary adj. Fancied. 
imbibe v. To drink or take in. 
imbroglio n. A misunderstanding attended by ill feeling, perplexity, or strife. 
imbrue v. To wet or moisten. 
imitation n. That which is made as a likeness or copy. 
imitator n. One who makes in imitation. 
immaculate adj. Without spot or blemish. 
immaterial adj. Of no essential consequence. 
immature adj. Not full-grown. 
immeasurable adj. Indefinitely extensive. 
immense adj. Very great in degree, extent, size, or quantity. 
immerse v. To plunge or dip entirely under water or other fluid. 
immersion n. The act of plunging or dipping entirely under water or another fluid. 
immigrant n. A foreigner who enters a country to settle there. 
immigrate v. To come into a country or region from a former habitat. 
imminence n. Impending evil or danger. 
imminent adj. Dangerous and close at hand. 
immiscible adj. Separating, as oil and water. 
immoral adj. Habitually engaged in licentious or lewd practices. 
immortalize v. To cause to last or to be known or remembered throughout a great or indefinite length of time. 
immovable adj. Steadfast. 
immune adj. Exempt, as from disease. 
immutable adj. Unchangeable. 
impair v. To cause to become less or worse. 
impalpable adj. Imperceptible to the touch. 
impartial adj. Unbiased. 
impassable adj. That can not be passed through or over. 
impassible adj. Not moved or affected by feeling. 
impassive adj. Unmoved by or not exhibiting feeling. 
impatience n. Unwillingness to brook delays or wait the natural course of things. 
impeccable adj. Blameless. 
impecunious adj. Having no money. 
impede v. To be an obstacle or to place obstacles in the way of. 
impel v. To drive or urge forward. 
impend v. To be imminent. 
imperative adj. Obligatory. 
imperceptible adj. Indiscernible. 
imperfectible adj. That can not be perfected. 
imperil v. To endanger. 
imperious adj. Insisting on obedience. 
impermissible adj. Not permissible. 
impersonal adj. Not relating to a particular person or thing. 
impersonate v. To appear or act in the character of. 
impersuadable adj. Unyielding. 
impertinence n. Rudeness. 
imperturbable adj. Calm. 
impervious adj. Impenetrable. 
impetuosity n. Rashness. 
impetuous adj. Impulsive. 
impetus n. Any impulse or incentive. 
impiety n. Irreverence toward God. 
impious adj. Characterized by irreverence or irreligion. 
implausible adj. Not plausible. 
impliable adj. Capable of being inferred. 
implicate v. To show or prove to be involved in or concerned 
implicit adj. Implied. 
imply v. To signify. 
impolitic adj. Inexpedient. 
importation n. The act or practice of bringing from one country into another. 
importunate adj. Urgent in character, request, or demand. 
importune v. To harass with persistent demands or entreaties. 
impotent adj. Destitute of or lacking in power, physical, moral, or intellectual. 
impoverish v. To make indigent or poor. 
impracticable adj. Not feasible. 
impregnable adj. That can not be taken by assault. 
impregnate v. To make pregnant. 
impromptu n. Anything done or said on the impulse of the moment. 
improper adj. Not appropriate, suitable, or becoming. 
impropriety n. The state or quality of being unfit, unseemly, or inappropriate. 
improvident adj. Lacking foresight or thrift. 
improvise v. To do anything extemporaneously or offhand. 
imprudent adj. Heedless. 
impudence n. Insolent disrespect. 
impugn v. To assail with arguments, insinuations, or accusations. 
impulsion n. Impetus. 
impulsive adj. Unpremeditated. 
impunity n. Freedom from punishment. 
impure adj. Tainted. 
impute v. To attribute. 
inaccessible adj. Difficult of approach. 
inaccurate adj. Not exactly according to the facts. 
inactive adj. Inert. 
inadequate adj. Insufficient. 
inadmissible adj. Not to be approved, considered, or allowed, as testimony. 
inadvertent adj. Accidental. 
inadvisable adj. Unadvisable. 
inane adj. Silly. 
inanimate adj. Destitute of animal life. 
inapprehensible adj. Not to be understood. 
inapt adj. Awkward or slow. 
inarticulate adj. Speechless. 
inaudible adj. That can not be heard. 
inborn adj. Implanted by nature. 
inbred adj. Innate. 
incandescence n. The state of being white or glowing with heat. 
incandescent adj. White or glowing with heat. 
incapacitate v. To deprive of power, capacity, competency, or qualification. 
incapacity n. Want of power to apprehend, understand, and manage. 
incarcerate v. To imprison. 
incendiary n. Chemical or person who starts a fire-literally or figuratively. 
incentive n. That which moves the mind or inflames the passions. 
inception n. The beginning. 
inceptive adj. Beginning. 
incessant adj. Unceasing. 
inchmeal adv. Piecemeal. 
inchoate adj. Incipient. 
inchoative n. That which begins, or expresses beginning. 
incidence n. Casual occurrence. 
incident n. A happening in general, especially one of little importance. 
incidentally adv. Without intention. 
incinerate v. To reduce to ashes. 
incipience n. Beginning. 
incipient adj. Initial. 
incisor n. A front or cutting tooth. 
incite v. To rouse to a particular action. 
incitement n. That which moves to action, or serves as an incentive or stimulus. 
incoercible adj. Incapable of being forced, constrained, or compelled. 
incoherence n. Want of connection, or agreement, as of parts or ideas in thought, speech, etc. 
incoherent adj. Not logically coordinated, as to parts, elements, or details. 
incombustible adj. That can not be burned. 
incomparable adj. Matchless. 
incompatible adj. Discordant. 
incompetence n. General lack of capacity or fitness. 
incompetent adj. Not having the abilities desired or necessary for any purpose. 
incomplete adj. Lacking some element, part, or adjunct necessary or required. 
incomprehensible adj. Not understandable. 
incompressible adj. Resisting all attempts to reduce volume by pressure. 
inconceivable adj. Incomprehensible. 
incongruous adj. Unsuitable for the time, place, or occasion. 
inconsequential adj. Valueless. 
inconsiderable adj. Small in quantity or importance. 
inconsistent adj. Contradictory. 
inconstant adj. Changeable. 
incontrovertible adj. Indisputable. 
inconvenient adj. Interfering with comfort or progress. 
indefensible adj. Untenable. 
indefinitely adv. In a vague or uncertain way. 
indelible adj. That can not be blotted out, effaced, destroyed, or removed. 
indescribable adj. That can not be described. 
indestructible adj. That can not be destroyed. 
indicant adj. That which points out. 
indicator n. One who or that which points out. 
indict v. To find and declare chargeable with crime. 
indigence n. Poverty. 
indigenous adj. Native. 
indigent adj. Poor. 
indigestible adj. Not digestible, or difficult to digest. 
indigestion n. Difficulty or failure in the alimentary canal in changing food into absorptive nutriment. 
indignant adj. Having such anger and scorn as is aroused by meanness or wickedness. 
indignity n. Unmerited contemptuous conduct or treatment. 
indiscernible adj. Not perceptible. 
indiscreet adj. Lacking wise judgment. 
indiscriminate adj. Promiscuous. 
indispensable adj. Necessary or requisite for the purpose. 
indistinct adj. Vague. 
indivertible adj. That can not be turned aside. 
indivisible adj. Not separable into parts. 
indolence n. Laziness. 
indolent adj. Habitually inactive or idle. 
indomitable adj. Unconquerable. 
induct v. To bring in. 
indulgence n. The yielding to inclination, passion, desire, or propensity in oneself or another. 
indulgent adj. Yielding to the desires or humor of oneself or those under one’s care. 
inebriate v. To intoxicate. 
inedible adj. Not good for food. 
ineffable adj. Unutterable. 
inefficient adj. Not accomplishing an intended purpose. 
inefficiency n. That which does not accomplish an intended purpose. 
ineligible adj. Not suitable to be selected or chosen. 
inept adj. Not fit or suitable. 
inert adj. Inanimate. 
inestimable adj. Above price. 
inevitable adj. Unavoidable. 
inexcusable adj. Not to be justified. 
inexhaustible adj. So large or furnishing so great a supply as not to be emptied, wasted, or spent. 
inexorable adj. Unrelenting. 
inexpedient adj. Unadvisable. 
inexpensive adj. Low-priced. 
inexperience n. Lack of or deficiency in experience. 
inexplicable adj. Such as can not be made plain. 
inexpressible adj. Unutterable. 
inextensible adj. Of unchangeable length or area. 
infallible adj. Exempt from error of judgment, as in opinion or statement. 
infamous adj. Publicly branded or notorious, as for vice, or crime. 
infamy n. Total loss or destitution of honor or reputation. 
inference n. The derivation of a judgment from any given material of knowledge on the ground of law. 
infernal adj. Akin to or befitting hell or its occupants. 
infest v. To be present in such numbers as to be a source of annoyance, trouble, or danger. 
infidel n. One who denies the existence of God. 
infidelity n. Disloyalty. 
infinite adj. Measureless. 
infinity n. Boundless or immeasurable extension or duration. 
infirm adj. Lacking in bodily or mental strength. 
infirmary n. A place for the reception or treatment of the sick. 
infirmity n. A physical, mental, or moral weakness or flaw. 
inflammable adj. Easily set on fire or excited. 
inflammation n. A morbid process in some part of the body characterized by heat, swelling, and pain. 
inflexible adj. That can not be altered or varied. 
influence n. Ability to sway the will of another. 
influential adj. Having the power to sway the will of another. 
influx n. Infusion. 
infrequence n. Rareness. 
infrequent adj. Uncommon. 
infringe v. To trespass upon. 
infuse v. To instill, introduce, or inculcate, as principles or qualities. 
infusion n. The act of imbuing, or pouring in. 
ingenious adj. Evincing skill, originality, or cleverness, as in contrivance or arrangement. 
ingenuity n. Cleverness in contriving, combining, or originating. 
ingenuous adj. Candid, frank, or open in character or quality. 
inglorious adj. Shameful. 
ingraft v. To set or implant deeply and firmly. 
ingratiate v. To win confidence or good graces for oneself. 
ingratitude n. Insensibility to kindness. 
ingredient n. Component. 
inherence n. The state of being permanently existing in something. 
inherent adj. Intrinsic. 
inhibit v. To hold back or in. 
inhospitable adj. Not disposed to entertain strangers gratuitously. 
inhuman adj. Savage. 
inhume v. To place in the earth, as a dead body. 
inimical adj. Adverse. 
iniquity n. Gross wrong or injustice. 
initiate v. To perform the first act or rite. 
inject v. To introduce, as a fluid, by injection. 
injunction n. Mandate. 
inkling n. A hint. 
inland adj. Remote from the sea. 
inlet n. A small body of water leading into a larger. 
inmost adj. Deepest within. 
innocuous adj. Harmless. 
innovate v. To introduce or strive to introduce new things. 
innuendo n. Insinuation. 
innumerable adj. Countless. 
inoffensive adj. Causing nothing displeasing or disturbing. 
inopportune adj. Unsuitable or inconvenient, especially as to time. 
inquire v. To ask information about. 
inquisition n. A court or tribunal for examination and punishment of heretics. 
inquisitive adj. Given to questioning, especially out of curiosity. 
inquisitor n. One who makes an investigation. 
inroad n. Forcible encroachment or trespass. 
insatiable adj. That desires or craves immoderately or unappeasably. 
inscribe v. To enter in a book, or on a list, roll, or document, by writing. 
inscrutable adj. Impenetrably mysterious or profound. 
insecure adj. Not assured of safety. 
insensible adj. Imperceptible. 
insentient adj. Lacking the power of feeling or perceiving. 
inseparable adj. That can not be separated. 
insidious adj. Working ill by slow and stealthy means. 
insight n. Intellectual discernment. 
insignificance n. Lack of import or of importance. 
insignificant adj. Without importance, force, or influence. 
insinuate v. To imply. 
insipid adj. Tasteless. 
insistence n. Urgency. 
insistent adj. Urgent. 
insolence n. Pride or haughtiness exhibited in contemptuous and overbearing treatment of others. 
insolent adj. Impudent. 
insomnia n. Sleeplessness. 
inspector n. An official appointed to examine or oversee any matter of public interest or importance. 
instance n. A single occurrence or happening of a given kind. 
instant n. A very brief portion of time. 
instantaneous adj. Done without perceptible lapse of time. 
instigate v. To provoke. 
instigator n. One who incites to evil. 
instill v. To infuse. 
instructive adj. Conveying knowledge. 
insufficiency n. Inadequacy. 
insufficient adj. Inadequate for some need, purpose, or use. 
insular adj. Pertaining to an island. 
insulate v. To place in a detached state or situation. 
insuperable adj. Invincible. 
insuppressible adj. Incapable of being concealed. 
insurgence n. Uprising. 
insurgent n. One who takes part in forcible opposition to the constituted authorities of a place. 
insurrection n. The state of being in active resistance to authority. 
intangible adj. Not perceptible to the touch. 
integrity n. Uprightness of character and soundness of moral principle. 
intellect n. The faculty of perception or thought. 
intellectual adj. Characterized by intelligence. 
intelligence n. Capacity to know or understand. 
intelligible adj. Comprehensible. 
intemperance n. Immoderate action or indulgence, as of the appetites. 
intension n. The act of stringing or stretching, or state of being strained. 
intensive adj. Adding emphasis or force. 
intention n. That upon which the mind is set. 
interact v. To act reciprocally. 
intercede v. To mediate between persons. 
intercept v. To interrupt the course of. 
intercession n. Entreaty in behalf of others. 
intercessor n. A mediator. 
interdict n. Authoritative act of prohibition. 
interim n. Time between acts or periods. 
interlocutor n. One who takes part in a conversation or oral discussion. 
interlude n. An action or event considered as coming between others of greater length. 
intermediate adj. Being in a middle place or degree or between extremes. 
interminable adj. Having no limit or end. 
intermission n. A recess. 
intermit v. To cause to cease temporarily. 
intermittent adj. A temporary discontinuance. 
interpolation n. Verbal interference. 
interpose v. To come between other things or persons. 
interposition n. A coming between. 
interpreter n. A person who makes intelligible the speech of a foreigner by oral translation. 
interrogate v. To examine formally by questioning. 
interrogative adj. Having the nature or form of a question. 
interrogatory n. A question or inquiry. 
interrupt v. To stop while in progress. 
intersect v. To cut through or into so as to divide. 
intervale n. A low tract of land between hills, especially along a river. 
intervene v. To interfere for some end. 
intestacy n. The condition resulting from one’s dying not having made a valid will. 
intestate adj. Not having made a valid will. 
intestine n. That part of the digestive tube below or behind the stomach, extending to the anus. 
intimacy n. Close or confidential friendship. 
intimidate v. To cause to become frightened. 
intolerable adj. Insufferable. 
intolerance n. Inability or unwillingness to bear or endure. 
intolerant adj. Bigoted. 
intoxicant n. Anything that unduly exhilarates or excites. 
intoxicate v. To make drunk. 
intracellular adj. Occurring or situated within a cell. 
intramural adj. Situated within the walls of a city. 
intrepid adj. Fearless and bold. 
intricacy n. Perplexity. 
intricate adj. Difficult to follow or understand. 
intrigue n. A plot or scheme, usually complicated and intended to accomplish something by secret ways. 
intrinsic adj. Inherent. 
introductory adj. Preliminary. 
introgression n. Entrance. 
intromit v. To insert. 
introspect v. To look into. 
introspection n. The act of observing and analyzing one’s own thoughts and feelings. 
introversion n. The act of turning or directing inward, physically or mentally. 
introvert v. To turn within. 
intrude v. To come in without leave or license. 
intrusion n. The act of entering without warrant or invitation; encroachment. 
intuition n. Instinctive knowledge or feeling. 
inundate v. To fill with an overflowing abundance. 
inundation n. Flood. 
inure v. To harden or toughen by use, exercise, or exposure. 
invalid adj. Having no force, weight, or cogency. 
invalid n. One who is disabled by illness or injury. 
invalidate v. To render of no force or effect. 
invaluable adj. Exceedingly precious. 
invariable adj. Unchangeable. 
invasion n. Encroachment, as by an act of intrusion or trespass. 
invective n. An utterance intended to cast censure, or reproach. 
inveigh v. To utter vehement censure or invective. 
inventive adj. Quick at contrivance. 
inverse adj. Contrary in tendency or direction. 
inversion n. Change of order so that the first shall become last and the last first. 
invert v. To turn inside out, upside down, or in opposite direction. 
investigator n. One who investigates. 
investor n. One who invests money. 
inveterate adj. Habitual. 
invidious adj. Showing or feeling envy. 
invigorate v. To animate. 
invincible adj. Not to be conquered, subdued, or overcome. 
inviolable adj. Incapable of being injured or disturbed. 
invoke v. To call on for assistance or protection. 
involuntary adj. Unwilling. 
involution n. Complication. 
involve v. To draw into entanglement, literally or figuratively. 
invulnerable adj. That can not be wounded or hurt. 
inwardly adv. With no outward manifestation. 
iota n. A small or insignificant mark or part. 
irascible adj. Prone to anger. 
irate adj. Moved to anger. 
ire n. Wrath. 
iridescence n. A many-colored appearance. 
iridescent adj. Exhibiting changing rainbow-colors due to the interference of the light. 
irk v. To afflict with pain, vexation, or fatigue. 
irksome adj. Wearisome. 
irony n. Censure or ridicule under cover of praise or compliment. 
irradiance n. Luster. 
irradiate v. To render clear and intelligible. 
irrational adj. Not possessed of reasoning powers or understanding. 
irreducible adj. That can not be lessened. 
irrefragable adj. That can not be refuted or disproved. 
irrefrangible adj. That can not be broken or violated. 
irrelevant adj. Inapplicable. 
irreligious adj. Indifferent or opposed to religion. 
irreparable adj. That can not be rectified or made amends for. 
irrepressible adj. That can not be restrained or kept down. 
irresistible adj. That can not be successfully withstood or opposed. 
irresponsible adj. Careless of or unable to meet responsibilities. 
irreverence n. The quality showing or expressing a deficiency of veneration, especially for sacred things. 
irreverent adj. Showing or expressing a deficiency of veneration, especially for sacred things. 
irreverential adj. Showing or expressing a deficiency of veneration, especially for sacred things. 
irreversible adj. Irrevocable. 
irrigant adj. Serving to water lands by artificial means. 
irrigate v. To water, as land, by ditches or other artificial means. 
irritable adj. Showing impatience or ill temper on little provocation. 
irritancy n. The quality of producing vexation. 
irritant n. A mechanical, chemical, or pathological agent of inflammation, pain, or tension. 
irritate v. To excite ill temper or impatience in. 
irruption n. Sudden invasion. 
isle n. An island. 
islet n. A little island. 
isobar n. A line joining points at which the barometric pressure is the same at a specified moment. 
isochronous adj. Relating to or denoting equal intervals of time. 
isolate v. To separate from others of its kind. 
isothermal adj. Having or marking equality of temperature. 
itinerant adj. Wandering. 
itinerary n. A detailed account or diary of a journey. 
itinerate v. To wander from place to place. 
jargon n. Confused, unintelligible speech or highly technical speech. 
jaundice n. A morbid condition, due to obstructed excretion of bile or characterized by yellowing of the skin.
jeopardize v. To imperil. 
Jingo n. One of a party in Great Britain in favor of spirited and demonstrative foreign policy. 
jocose adj. Done or made in jest. 
jocular adj. Inclined to joke. 
joggle n. A sudden irregular shake or a push causing such a shake. 
journalize v. To keep a diary. 
jovial adj. Merry. 
jubilation n. Exultation. 
judgment n. The faculty by the exercise of which a deliberate conclusion is reached. 
judicature n. Distribution and administration of justice by trial and judgment. 
judicial adj. Pertaining to the administration of justice. 
judiciary n. That department of government which administers the law relating to civil and criminal justice. 
judicious adj. Prudent. 
juggle v. To play tricks of sleight of hand. 
jugglery n. The art or practice of sleight of hand. 
jugular adj. Pertaining to the throat. 
juicy adj. Succulent. 
junction n. The condition of being joined. 
juncture n. An articulation, joint, or seam. 
junta n. A council or assembly that deliberates in secret upon the affairs of government. 
juridical adj. Assumed by law to exist. 
jurisdiction n. Lawful power or right to exercise official authority. 
jurisprudence n. The science of rights in accordance with positive law. 
juror n. One who serves on a jury or is sworn in for jury duty in a court of justice. 
joust v. To engage in a tilt with lances on horseback. 
justification n. Vindication. 
juvenile adj. Characteristic of youth. 
juxtapose v. To place close together. 
keepsake n. Anything kept or given to be kept for the sake of the giver. 
kerchief n. A square of linen, silk, or other material, used as a covering for the head or neck. 
kernel n. A grain or seed. 
kiln n. An oven or furnace for baking, burning, or drying industrial products. 
kiloliter n. One thousand liters. 
kilometer n. A length of 1,000 meters. 
kilowatt n. One thousand watts. 
kimono n. A loose robe, fastening with a sash, the principal outer garment in Japan. 
kind-hearted adj. Having a kind and sympathetic nature. 
kingling n. A petty king. 
kingship n. Royal state. 
kinsfolk n. pl. Relatives. 
knavery n. Deceitfulness in dealing. 
knead v. To mix and work into a homogeneous mass, especially with the hands. 
knickknack n. A small article, more for ornament that use. 
knight errant n. One of the wandering knights who in the middle ages went forth in search of adventure. 
knighthood n. Chivalry. 
laborious adj. Toilsome. 
labyrinth n. A maze. 
lacerate v. To tear rudely or raggedly. 
lackadaisical adj. Listless. 
lactation n. The secretion of milk. 
lacteal adj. Milky. 
lactic adj. Pertaining to milk. 
laddie n. A lad. 
ladle n. A cup-shaped vessel with a long handle, intended for dipping up and pouring liquids. 
laggard adj. Falling behind. 
landholder n. Landowner. 
landlord n. A man who owns and lets a tenement or tenements. 
landmark n. A familiar object in the landscape serving as a guide to an area otherwise easily lost track of. 
landscape n. A rural view, especially one of picturesque effect, as seen from a distance or an elevation. 
languid adj. Relaxed. 
languor n. Lassitude of body or depression. 
lapse n. A slight deviation from what is right, proper, or just. 
lascivious adj. Lustful. 
lassie n. A little lass. 
latent adj. Dormant. 
latency n. The state of being dormant. 
later adv. At a subsequent time. 
lateral adj. Directed toward the side. 
latish adj. Rather late. 
lattice n. Openwork of metal or wood, formed by crossing or interlacing strips or bars. 
laud v. To praise in words or song. 
laudable adj. Praiseworthy. 
laudation n. High praise. 
laudatory adj. Pertaining to, expressing, or containing praise. 
laundress n. Washerwoman. 
laureate adj. Crowned with laurel, as a mark of distinction. 
lave v. To wash or bathe. 
lawgiver n. A legislator. 
lawmaker n. A legislator. 
lax adj. Not stringent or energetic. 
laxative adj. Having power to open or loosen the bowels. 
lea n. A field. 
leaflet n. A little leaf or a booklet. 
leaven v. To make light by fermentation, as dough. 
leeward n. That side or direction toward which the wind blows. 
left-handed adj. Using the left hand or arm more dexterously than the right. 
legacy n. A bequest. 
legalize v. To give the authority of law to. 
legging n. A covering for the leg. 
legible adj. That may be read with ease. 
legionary n. A member of an ancient Roman legion or of the modern French Legion of Honor. 
legislate v. To make or enact a law or laws. 
legislative adj. That makes or enacts laws. 
legislator n. A lawgiver. 
legitimacy n. Accordance with law. 
legitimate adj. Having the sanction of law or established custom. 
leisure n. Spare time. 
leniency n. Forbearance. 
lenient adj. Not harsh. 
leonine adj. Like a lion. 
lethargy n. Prolonged sluggishness of body or mind. 
levee n. An embankment beside a river or stream or an arm of the sea, to prevent overflow. 
lever n. That which exerts, or through which one may exert great power. 
leviathan n. Any large animal, as a whale. 
levity n. Frivolity. 
levy v. To impose and collect by force or threat of force. 
lewd adj. Characterized by lust or lasciviousness. 
lexicographer n. One who makes dictionaries. 
lexicography n. The making of dictionaries. 
lexicon n. A dictionary. 
liable adj. Justly or legally responsible. 
libel n. Defamation. 
liberalism n. Opposition to conservatism. 
liberate v. To set free or release from bondage. 
licentious adj. Wanton. 
licit adj. Lawful. 
liege adj. Sovereign. 
lien n. A legal claim or hold on property, as security for a debt or charge. 
lieu n. Stead. 
lifelike adj. Realistic. 
lifelong adj. Lasting or continuous through life. 
lifetime n. The time that life continues. 
ligament n. That which binds objects together. 
ligature n. Anything that constricts, or serves for binding or tying. 
light-hearted adj. Free from care. 
ligneous adj. Having the texture of appearance of wood. 
likelihood n. A probability. 
likely adj. Plausible. 
liking n. Fondness. 
limitation n. A restriction. 
linear adj. Of the nature of a line. 
liner n. A vessel belonging to a steamship-line. 
lingo n. Language. 
lingua n. The tongue. 
lingual adj. Pertaining to the use of the tongue in utterance. 
linguist n. One who is acquainted with several languages. 
linguistics n. The science of languages, or of the origin, history, and significance of words. 
liniment n. A liquid preparation for rubbing on the skin in cases of bruises, inflammation, etc. 
liquefacient adj. Possessing a liquefying nature or power. 
liquefy v. To convert into a liquid or into liquid form. 
liqueur n. An alcoholic cordial sweetened and flavored with aromatic substances. 
liquidate v. To deliver the amount or value of. 
liquor n. Any alcoholic or intoxicating liquid. 
listless adj. Inattentive. 
literacy n. The state or condition of knowing how to read and write. 
literal adj. Following the exact words. 
literature n. The written or printed productions of the human mind collectively. 
lithe adj. Supple. 
lithesome adj. Nimble. 
lithograph n. A print made by printing from stone. 
lithotype n. In engraving, an etched stone surface for printing. 
litigant n. A party to a lawsuit. 
litigate v. To cause to become the subject-matter of a suit at law. 
litigious adj. Quarrelsome. 
littoral adj. Of, pertaining to, or living on a shore. 
liturgy n. A ritual. 
livelihood n. Means of subsistence. 
livid adj. Black-and-blue, as contused flesh. 
loam n. A non-coherent mixture of sand and clay. 
loath adj. Averse. 
loathe v. To abominate. 
locative adj. Indicating place, or the place where or wherein an action occurs. 
loch n. A lake. 
locomotion n. The act or power of moving from one place to another. 
lode n. A somewhat continuous unstratified metal- bearing vein. 
lodgment n. The act of furnishing with temporary quarters. 
logic n. The science of correct thinking. 
logical adj. Capable of or characterized by clear reasoning. 
logician n. An expert reasoner. 
loiterer n. One who consumes time idly. 
loneliness n. Solitude. 
longevity n. Unusually prolonged life. 
loot v. To plunder. 
loquacious adj. Talkative. 
lordling n. A little lord. 
lough n. A lake or loch. 
louse n. A small insect parasitic on and sucking the blood of mammals. 
lovable adj. Amiable. 
low-spirited adj. Despondent. 
lowly adv. Rudely. 
lucid adj. Mentally sound. 
lucrative adj. Highly profitable. 
ludicrous adj. Laughable. 
luminary n. One of the heavenly bodies as a source of light. 
luminescent adj. Showing increase of light. 
luminescence n. Showing increase. 
luminosity n. The quality of giving or radiating light. 
luminous adj. Giving or radiating light. 
lunacy n. Mental unsoundness. 
lunar adj. Pertaining to the moon. 
lunatic n. An insane person. 
lune n. The moon. 
lurid adj. Ghastly and sensational. 
luscious adj. Rich, sweet, and delicious. 
lustrous adj. Shining. 
luxuriance n. Excessive or superfluous growth or quantity. 
luxuriant adj. Abundant or superabundant in growth. 
luxuriate v. To live sumptuously. 
lying n. Untruthfulness. 
lyre n. One of the most ancient of stringed instruments of the harp class. 
lyric adj. Fitted for expression in song. 
macadamize v. To cover or pave, as a path or roadway, with small broken stone. 
machinery n. The parts of a machine or engine, taken collectively. 
machinist n. One who makes or repairs machines, or uses metal-working tools. 
macrocosm n. The whole of any sphere or department of nature or knowledge to which man is related. 
madden v. To inflame with passion. 
Madonna n. A painted or sculptured representation of the Virgin, usually with the infant Jesus. 
magician n. A sorcerer. 
magisterial adj. Having an air of authority. 
magistracy n. The office or dignity of a magistrate. 
magnanimous adj. Generous in treating or judging others. 
magnate n. A person of rank or importance. 
magnet n. A body possessing that peculiar form of polarity found in nature in the lodestone. 
magnetize v. To make a magnet of, permanently, or temporarily. 
magnificence n. The exhibition of greatness of action, character, intellect, wealth, or power. 
magnificent adj. Grand or majestic in appearance, quality, or action. 
magnitude n. Importance. 
maharaja n. A great Hindu prince. 
maidenhood n. Virginity. 
maintain v. To hold or preserve in any particular state or condition. 
maintenance n. That which supports or sustains. 
maize n. Indian corn: usually in the United States called simply corn. 
makeup n. The arrangements or combination of the parts of which anything is composed. 
malady n. Any physical disease or disorder, especially a chronic or deep-seated one. 
malaria n. A fever characterized by alternating chills, fever, and sweating. 
malcontent n. One who is dissatisfied with the existing state of affairs. 
malediction n. The calling down of a curse or curses. 
malefactor n. One who injures another. 
maleficent adj. Mischievous. 
malevolence n. Ill will. 
malevolent adj. Wishing evil to others. 
malign v. To speak evil of, especially to do so falsely and severely. 
malignant adj. Evil in nature or tending to do great harm or mischief. 
malleable adj. Pliant. 
mallet n. A wooden hammer. 
maltreat v. To treat ill, unkindly, roughly, or abusively. 
man-trap n. A place or structure dangerous to human life. 
mandate n. A command. 
mandatory adj. Expressive of positive command, as distinguished from merely directory. 
mane n. The long hair growing upon and about the neck of certain animals, as the horse and the lion. 
man-eater n. An animal that devours human beings. 
maneuver v. To make adroit or artful moves: manage affairs by strategy. 
mania n. Insanity. 
maniac n. a person raving with madness. 
manifesto n. A public declaration, making announcement, explanation or defense of intentions, or motives. 
manlike adj. Like a man. 
manliness n. The qualities characteristic of a true man, as bravery, resolution, etc. 
mannerism n. Constant or excessive adherence to one manner, style, or peculiarity, as of action or conduct. 
manor n. The landed estate of a lord or nobleman. 
mantel n. The facing, sometimes richly ornamented, about a fireplace, including the usual shelf above it. 
mantle n. A cloak. 
manufacturer n. A person engaged in manufacturing as a business. 
manumission n. Emancipation. 
manumit v. To set free from bondage. 
marine adj. Of or pertaining to the sea or matters connected with the sea. 
maritime adj. Situated on or near the sea. 
maroon v. To put ashore and abandon (a person) on a desolate coast or island. 
martial adj. Pertaining to war or military operations. 
Martian adj. Pertaining to Mars, either the Roman god of war or the planet. 
martyrdom n. Submission to death or persecution for the sake of faith or principle. 
marvel v. To be astonished and perplexed because of (something). 
masonry n. The art or work of constructing, as buildings, walls, etc., with regularly arranged stones. 
masquerade n. A social party composed of persons masked and costumed so as to be disguised. 
massacre n. The unnecessary and indiscriminate killing of human beings. 
massive adj. Of considerable bulk and weight. 
masterpiece n. A superior production. 
mastery n. The attainment of superior skill. 
material n. That of which anything is composed or may be constructed. 
materialize v. To take perceptible or substantial form. 
maternal adj. Pertaining or peculiar to a mother or to motherhood. 
matinee n. An entertainment (especially theatrical) held in the daytime. 
matricide n. The killing, especially the murdering, of one’s mother. 
matrimony n. The union of a man and a woman in marriage. 
matrix n. That which contains and gives shape or form to anything. 
matter of fact n. Something that has actual and undeniable existence or reality. 
maudlin adj. Foolishly and tearfully affectionate. 
mausoleum n. A tomb of more than ordinary size or architectural pretensions. 
mawkish adj. Sickening or insipid. 
maxim n. A principle accepted as true and acted on as a rule or guide. 
maze n. A labyrinth. 
mead n. A meadow. 
meager adj. scanty. 
mealy-mouthed adj. Afraid to express facts or opinions plainly. 
meander v. To wind and turn while proceeding in a course. 
mechanics n. The branch of physics that treats the phenomena caused by the action of forces. 
medallion n. A large medal. 
meddlesome adj. Interfering. 
medial adj. Of or pertaining to the middle. 
mediate v. To effect by negotiating as an agent between parties. 
medicine n. A substance possessing or reputed to possess curative or remedial properties. 
medieval adj. Belonging or relating to or descriptive of the middle ages. 
mediocre adj. Ordinary. 
meditation n. The turning or revolving of a subject in the mind. 
medley n. A composition of different songs or parts of songs arranged to run as a continuous whole. 
meliorate v. To make better or improve, as in quality or social or physical condition. 
mellifluous adj. Sweetly or smoothly flowing. 
melodious adj. Characterized by a sweet succession of sounds. 
melodrama n. A drama with a romantic story or plot and sensational situation and incidents. 
memento n. A souvenir. 
memorable adj. Noteworthy. 
menace n. A threat. 
menagerie n. A collection of wild animals, especially when kept for exhibition. 
mendacious adj. Untrue. 
mendicant n. A beggar. 
mentality n. Intellectuality. 
mentor n. A wise and faithful teacher, guide, and friend. 
mercantile adj. Conducted or acting on business principles; commercial. 
mercenary adj. Greedy 
merciful adj. Disposed to pity and forgive. 
merciless adj. Cruel. 
meretricious adj. Alluring by false or gaudy show. 
mesmerize v. To hypnotize. 
messieurs n. pl. Gentlemen. 
metal n. An element that forms a base by combining with oxygen, is usually hard, heavy, and lustrous. 
metallurgy n. The art or science of extracting a metal from ores, as by smelting. 
metamorphosis n. A passing from one form or shape into another. 
metaphor n. A figure of speech in which one object is likened to another, by speaking as if the other. 
metaphysical adj. Philosophical. 
metaphysician n. One skilled in metaphysics. 
metaphysics n. The principles of philosophy as applied to explain the methods of any particular science. 
mete v. To apportion. 
metempsychosis n. Transition of the soul of a human being at death into another body, whether human or beast. 
meticulous adj. Over-cautious. 
metonymy n. A figure of speech that consists in the naming of a thing by one of its attributes. 
metric adj. Relating to measurement. 
metronome n. An instrument for indicating and marking exact time in music. 
metropolis n. A chief city, either the capital or the largest or most important city of a state. 
metropolitan adj. Pertaining to a chief city. 
mettle n. Courage. 
mettlesome adj. Having courage or spirit. 
microcosm n. The world or universe on a small scale. 
micrometer n. An instrument for measuring very small angles or dimensions. 
microphone n. An apparatus for magnifying faint sounds. 
microscope n. An instrument for assisting the eye in the vision of minute objects or features of objects. 
microscopic adj. Adapted to or characterized by minute observation. 
microscopy n. The art of examing objects with the microscope. 
midsummer n. The middle of the summer. 
midwife n. A woman who makes a business of assisting at childbirth. 
mien n. The external appearance or manner of a person. 
migrant adj. Wandering. 
migrate v. To remove or pass from one country, region, or habitat to another. 
migratory adj. Wandering. 
mileage n. A distance in miles. 
militant adj. Of a warlike or combative disposition or tendency. 
militarism n. A policy of maintaining great standing armies. 
militate v. To have weight or influence (in determining a question). 
militia n. Those citizens, collectively, who are enrolled and drilled in temporary military organizations. 
Milky Way n. The galaxy. 
millet n. A grass cultivated for forage and cereal. 
mimic v. To imitate the speech or actions of. 
miniature adj. Much smaller than reality or that the normal size. 
minimize v. To reduce to the smallest possible amount or degree. 
minion n. A servile favorite. 
ministration n. Any religious ceremonial. 
ministry n. A service. 
minority n. The smaller in number of two portions into which a number or a group is divided. 
minute adj. Exceedingly small in extent or quantity. 
minutia n. A small or unimportant particular or detail. 
mirage n. An optical effect looking like a sheet of water in the desert. 
misadventure n. An unlucky accident. 
misanthropic adj. Hating mankind. 
misanthropy n. Hatred of mankind. 
misapprehend v. To misunderstand. 
misbehave v. To behave ill. 
misbehavior n. Ill or improper behavior. 
mischievous adj. Fond of tricks. 
miscount v. To make a mistake in counting. 
miscreant n. A villain. 
misdeed n. A wrong or improper act. 
misdemeanor n. Evil conduct, small crime. 
miser n. A person given to saving and hoarding unduly. 
mishap n. Misfortune. 
misinterpret v. To misunderstand. 
mislay v. To misplace. 
mismanage v. To manage badly, improperly, or unskillfully. 
misnomer n. A name wrongly or mistakenly applied. 
misogamy n. Hatred of marriage. 
misogyny n. Hatred of women. 
misplace v. To put into a wrong place. 
misrepresent v. To give a wrong impression. 
misrule v. To misgovern. 
missal n. The book containing the service for the celebration of mass. 
missile n. Any object, especially a weapon, thrown or intended to be thrown. 
missive n. A message in writing. 
mistrust v. To regard with suspicion or jealousy. 
misty adj. Lacking clearness 
misunderstand v. To Take in a wrong sense. 
misuse v. To maltreat. 
mite n. A very small amount, portion, or particle. 
miter n. The junction of two bodies at an equally divided angle. 
mitigate v. To make milder or more endurable. 
mnemonics n. A system of principles and formulas designed to assist the recollection in certain instances. 
moat n. A ditch on the outside of a fortress wall. 
mobocracy n. Lawless control of public affairs by the mob or populace. 
moccasin n. A foot-covering made of soft leather or buckskin. 
mockery n. Ridicule. 
moderation n. Temperance. 
moderator n. The presiding officer of a meeting. 
modernity n. The state or character of being modern. 
modernize v. To make characteristic of the present or of recent times. 
modification n. A change. 
modify v. To make somewhat different. 
modish adj. Fashionable. 
modulate v. To vary in tone, inflection, pitch or other quality of sound. 
mollify v. To soothe. 
molt v. To cast off, as hair, feathers, etc. 
momentary adj. Lasting but a short time. 
momentous adj. Very significant. 
momentum n. An impetus. 
monarchy n. Government by a single, sovereign ruler. 
monastery n. A dwelling-place occupied in common by persons under religious vows of seclusion. 
monetary adj. Financial. 
mongrel n. The progeny resulting from the crossing of different breeds or varieties. 
monition n. Friendly counsel given by way of warning and implying caution or reproof. 
monitory n. Admonition or warning. 
monocracy n. Government by a single person. 
monogamy n. The habit of pairing, or having but one mate. 
monogram n. A character consisting of two or more letters interwoven into one, usually initials of a name. 
monograph n. A treatise discussing a single subject or branch of a subject. 
monolith n. Any structure or sculpture in stone formed of a single piece. 
monologue n. A story or drama told or performed by one person. 
monomania n. The unreasonable pursuit of one idea. 
monopoly n. The control of a thing, as a commodity, to enable a person to raise its price. 
monosyllable n. A word of one syllable. 
monotone n. The sameness or monotony of utterance. 
monotonous adj. Unchanging and tedious. 
monotony n. A lack of variety. 
monsieur n. A French title of respect, equivalent to Mr. and sir. 
monstrosity n. Anything unnaturally huge or distorted. 
moonbeam n. A ray of moonlight. 
morale n. A state of mind with reference to confidence, courage, zeal, and the like. 
moralist n. A writer on ethics. 
morality n. Virtue. 
moralize v. To render virtuous. 
moratorium n. An emergency legislation authorizing a government suspend some action temporarily. 
morbid adj. Caused by or denoting a diseased or unsound condition of body or mind. 
mordacious adj. Biting or giving to biting. 
mordant adj. Biting. 
moribund adj. On the point of dying. 
morose adj. Gloomy. 
morphology n. the science of organic forms. 
motley adj. Composed of heterogeneous or inharmonious elements. 
motto n. An expressive word or pithy sentence enunciating some guiding rule of life, or faith. 
mountaineer n. One who travels among or climbs mountains for pleasure or exercise. 
mountainous adj. Full of or abounding in mountains. 
mouthful n. As much as can be or is usually put into the or exercise. 
muddle v. To confuse or becloud, especially with or as with drink. 
muffle v. To deaden the sound of, as by wraps. 
mulatto n. The offspring of a white person and a black person. 
muleteer n. A mule-driver. 
multiform adj. Having many shapes, or appearances. 
multiplicity n. the condition of being manifold or very various. 
mundane adj. Worldly, as opposed to spiritual or celestial. 
municipal adj. Of or pertaining to a town or city, or to its corporate or local government. 
municipality n. A district enjoying municipal government. 
munificence n. A giving characterized by generous motives and extraordinary liberality. 
munificent adj. Extraordinarily generous. 
muster n. An assemblage or review of troops for parade or inspection, or for numbering off. 
mutation n. The act or process of change. 
mutilate v. To disfigure. 
mutiny n. Rebellion against lawful or constituted authority. 
myriad n. A vast indefinite number. 
mystic n. One who professes direct divine illumination, or relies upon meditation to acquire truth. 
mystification n. The act of artfully perplexing. 
myth n. A fictitious narrative presented as historical, but without any basis of fact. 
mythology n. The whole body of legends cherished by a race concerning gods and heroes. 
nameless adj. Having no fame or reputation. 
naphtha n. A light, colorless, volatile, inflammable oil used as a solvent, as in manufacture of paints. 
Narcissus n. The son of the Athenian river-god Cephisus, fabled to have fallen in love with his reflection.
narrate v. To tell a story. 
narration n. The act of recounting the particulars of an event in the order of time or occurrence. 
narrative n. An orderly continuous account of the successive particulars of an event. 
narrator n. One who narrates anything. 
narrow-minded adj. Characterized by illiberal views or sentiments. 
nasal adj. Pertaining to the nose. 
natal adj. Pertaining to one’s birth. 
nationality n. A connection with a particular nation. 
naturally adv. According to the usual order of things. 
nausea n. An affection of the stomach producing dizziness and usually an impulse to vomit 
nauseate v. To cause to loathe. 
nauseous adj. Loathsome. 
nautical adj. Pertaining to ships, seamen, or navigation. 
naval adj. Pertaining to ships. 
navel n. The depression on the abdomen where the umbilical cord of the fetus was attached. 
navigable adj. Capable of commercial navigation. 
navigate v. To traverse by ship. 
nebula n. A gaseous body of unorganized stellar substance. 
necessary adj. Indispensably requisite or absolutely needed to accomplish a desired result. 
necessitate v. To render indispensable. 
necessity n. That which is indispensably requisite to an end desired. 
necrology n. A list of persons who have died in a certain place or time. 
necromancer n. One who practices the art of foretelling the future by means of communication with the dead. 
necropolis n. A city of the dead. 
necrosis n. the death of part of the body. 
nectar n. Any especially sweet and delicious drink. 
nectarine n. A variety of the peach. 
needlework n. Embroidery. 
needy adj. Being in need, want, or poverty. 
nefarious adj. Wicked in the extreme. 
negate v. To deny. 
negation n. The act of denying or of asserting the falsity of a proposition. 
neglectful adj. Exhibiting or indicating omission. 
negligee n. A loose gown worn by women. 
negligence n. Omission of that which ought to be done. 
negligent adj. Apt to omit what ought to be done. 
negligible adj. Transferable by assignment, endorsement, or delivery. 
negotiable v. To bargain with others for an agreement, as for a treaty or transfer of property. 
Nemesis n. A goddess; divinity of chastisement and vengeance. 
neocracy n. Government administered by new or untried persons. 
neo-Darwinsim n. Darwinism as modified and extended by more recent students. 
neo-Latin n. Modernized Latin. 
neopaganism n. A new or revived paganism. 
Neolithic adj. Pertaining to the later stone age. 
neology n. The coining or using of new words or new meanings of words. 
neophyte adj. Having the character of a beginner. 
nestle v. To adjust cozily in snug quarters. 
nestling adj. Recently hatched. 
nettle v. To excite sensations of uneasiness or displeasure in. 
network n. Anything that presents a system of cross- lines. 
neural adj. Pertaining to the nerves or nervous system. 
neurology n. The science of the nervous system. 
neuter adj. Neither masculine nor feminine. 
neutral adj. Belonging to or under control of neither of two contestants. 
nevertheless conj. Notwithstanding. 
Newtonian adj. Of or pertaining to Sir Isaac Newton, the English philosopher. 
niggardly adj. Stingy. (no longer acceptable to use) 
nihilist n. An advocate of the doctrine that nothing either exists or can be known. 
nil n. Nothing 
nimble adj. Light and quick in motion or action. 
nit n. The egg of a louse or some other insect. 
nocturnal adj. Of or pertaining to the night. 
noiseless adj. Silent. 
noisome adj. Very offensive, particularly to the sense of smell. 
noisy adj. Clamorous. 
nomad adj. Having no fixed abode. 
nomic adj. Usual or customary. 
nominal adj. Trivial. 
nominate v. To designate as a candidate for any office. 
nomination n. The act or ceremony of naming a man or woman for office. 
nominee n. One who receives a nomination. 
non-existent n. That which does not exist. 
non-resident adj. Not residing within a given jurisdiction. 
nonchalance n. A state of mind indicating lack of interest. 
non-combatant n. One attached to the army or navy, but having duties other than that of fighting. 
nondescript adj. Indescribable. 
nonentity n. A person or thing of little or no account. 
nonpareil n. One who or that which is of unequaled excellence. 
norm n. A model. 
normalcy n. The state of being normal. 
Norman adj. Of or peculiar to Normandy, in northern France. 
nostrum n. Any scheme or recipe of a charlatan character. 
noticeable adj. Perceptible. 
notorious adj. Unfavorably known to the general public. 
novellette n. A short novel. 
novice n. A beginner in any business or occupation. 
nowadays adv. In the present time or age. 
nowhere adv. In no place or state. 
noxious adj. Hurtful. 
nuance n. A slight degree of difference in anything perceptible to the sense of the mind. 
nucleus n. A central point or part about which matter is aggregated. 
nude adj. Naked. 
nugatory adj. Having no power or force. 
nuisance n. That which annoys, vexes, or irritates. 
numeration n. The act or art of reading or naming numbers. 
numerical adj. Of or pertaining to number. 
nunnery n. A convent for nuns. 
nuptial adj. Of or pertaining to marriage, especially to the marriage ceremony. 
nurture n. The process of fostering or promoting growth. 
nutriment n. That which nourishes. 
nutritive adj. Having nutritious properties. 
oaken adj. Made of or from oak. 
oakum n. Hemp-fiber obtained by untwisting and picking out loosely the yarns of old hemp rope. 
obdurate adj. Impassive to feelings of humanity or pity. 
obelisk n. A square shaft with pyramidal top, usually monumental or commemorative. 
obese adj. Exceedingly fat. 
obesity n. Excessive fatness. 
obituary adj. A published notice of a death. 
objective adj. Grasping and representing facts as they are. 
objector n. One who objects, as to a proposition, measure, or ruling. 
obligate v. To hold to the fulfillment of duty. 
obligatory adj. Binding in law or conscience. 
oblique adj. Slanting; said of lines. 
obliterate v. To cause to disappear. 
oblivion n. The state of having passed out of the memory or of being utterly forgotten. 
oblong adj. Longer than broad: applied most commonly to rectangular objects considerably elongated 
obnoxious adj. Detestable. 
obsequies n. Funeral rites. 
obsequious adj. Showing a servile readiness to fall in with the wishes or will of another. 
observance n. A traditional form or customary act. 
observant adj. Quick to notice. 
observatory n. A building designed for systematic astronomical observations. 
obsolescence n. The condition or process of gradually falling into disuse. 
obsolescent adj. Passing out of use, as a word. 
obsolete adj. No longer practiced or accepted. 
obstetrician n. A practitioner of midwifery. 
obstetrics n. The branch of medical science concerned with the treatment and care of women during pregnancy. 
obstinacy n. Stubborn adherence to opinion, arising from conceit or the desire to have one’s own way. 
obstreperous adj. Boisterous. 
obstruct v. To fill with impediments so as to prevent passage, either wholly or in part. 
obstruction n. Hindrance. 
obtrude v. To be pushed or to push oneself into undue prominence. 
obtrusive adj. Tending to be pushed or to push oneself into undue prominence. 
obvert v. To turn the front or principal side of (a thing) toward any person or object. 
obviate v. To clear away or provide for, as an objection or difficulty. 
occasion n. An important event or celebration. 
Occident n. The countries lying west of Asia and the Turkish dominions. 
occlude v. To absorb, as a gas by a metal. 
occult adj. Existing but not immediately perceptible. 
occupant n. A tenant in possession of property, as distinguished from the actual owner. 
occurrence n. A happening. 
octagon n. A figure with eight sides and eight angles. 
octave n. A note at this interval above or below any other, considered in relation to that other. 
octavo n. A book, or collection of paper in which the sheets are so folded as to make eight leaves. 
octogenarian adj. A person of between eighty and ninety years. 
ocular adj. Of or pertaining to the eye. 
oculist n. One versed or skilled in treating diseases of the eye. 
oddity n. An eccentricity. 
ode n. The form of lyric poetry anciently intended to be sung. 
odious adj. Hateful. 
odium n. A feeling of extreme repugnance, or of dislike and disgust. 
odoriferous adj. Having or diffusing an odor or scent, especially an agreeable one. 
odorous adj. Having an odor, especially a fragrant one. 
off adj. Farther or more distant. 
offhand adv. Without preparation. 
officiate v. To act as an officer or leader. 
officious adj. Intermeddling with what is not one’s concern. 
offshoot n. Something that branches off from the parent stock. 
ogre n. A demon or monster that was supposed to devour human beings. 
ointment n. A fatty preparation with a butter-like consistency in which a medicinal substance exists.
olfactory adj. of or pertaining to the sense of smell. 
olive-branch n. A branch of the olive-tree, as an emblem of peace. 
ominous adj. Portentous. 
omission n. Exclusion. 
omnipotence n. Unlimited and universal power. 
Omnipotent adj. Possessed of unlimited and universal power. 
omniscience n. Unlimited or infinite knowledge. 
omniscient adj. Characterized by unlimited or infinite knowledge. 
omnivorous adj. Eating or living upon food of all kinds indiscriminately. 
onerous adj. Burdensome or oppressive. 
onrush n. Onset. 
onset n. An assault, especially of troops, upon an enemy or fortification. 
onslaught n. A violent onset. 
onus n. A burden or responsibility. 
opalescence n. The property of combined refraction and reflection of light, resulting in smoky tints. 
opaque adj. Impervious to light. 
operate v. To put in action and supervise the working of. 
operative adj. Active. 
operator n. One who works with or controls some machine or scientific apparatus. 
operetta n. A humorous play in dialogue and music, of more than one act. 
opinion n. A conclusion or judgment held with confidence, but falling short of positive knowledge. 
opponent n. One who supports the opposite side in a debate, discussion, struggle, or sport. 
opportune adj. Especially fit as occurring, said, or done at the right moment. 
opportunist n. One who takes advantage of circumstances to gain his ends. 
opportunity n. Favorable or advantageous chance or opening. 
opposite adj. Radically different or contrary in action or movement. 
opprobrium n. The state of being scornfully reproached or accused of evil. 
optic n. Pertaining to the eye or vision. 
optician n. One who makes or deals in optical instruments or eye-glasses. 
optics n. The science that treats of light and vision, and all that is connected with sight. 
optimism n. The view that everything in nature and the history of mankind is ordered for the best. 
option n. The right, power, or liberty of choosing. 
optometry n. Measurement of the powers of vision. 
opulence n. Affluence. 
opulent adj. Wealthy. 
oral adj. Uttered through the mouth. 
orate v. To deliver an elaborate or formal public speech. 
oration n. An elaborate or formal public speech. 
orator n. One who delivers an elaborate or formal speech. 
oratorio n. A composition for solo voices, chorus, and orchestra, generally taken from the Scriptures. 
oratory n. The art of public speaking. 
ordeal n. Anything that severely tests courage, strength, patience, conscience, etc. 
ordinal n. That form of the numeral that shows the order of anything in a series, as first, second, third. 
ordination n. A consecration to the ministry. 
ordnance n. A general name for all kinds of weapons and their appliances used in war. 
orgies n. Wild or wanton revelry. 
origin n. The beginning of that which becomes or is made to be. 
original adj. Not copied nor produced by imitation. 
originate v. To cause or constitute the beginning or first stage of the existence of. 
ornate adj. Ornamented to a marked degree. 
orthodox adj. Holding the commonly accepted faith. 
orthodoxy n. Acceptance of the common faith. 
orthogonal adj. Having or determined by right angles. 
orthopedic adj. Relating to the correcting or preventing of deformity 
orthopedist n. One who practices the correcting or preventing of deformity 
oscillate v. To swing back and forth. 
osculate v. To kiss. 
ossify v. to convert into bone. 
ostentation n. A display dictated by vanity and intended to invite applause or flattery. 
ostracism n. Exclusion from intercourse or favor, as in society or politics. 
ostracize v. To exclude from public or private favor. 
ought v. To be under moral obligation to be or do. 
oust v. To eject. 
out-and-out adv. Genuinely. 
outbreak n. A sudden and violent breaking forth, as of something that has been pent up or restrained. 
outburst n. A violent issue, especially of passion in an individual. 
outcast n. One rejected and despised, especially socially. 
outcry n. A vehement or loud cry or clamor. 
outdo v. To surpass. 
outlandish adj. Of barbarous, uncouth, and unfamiliar aspect or action. 
outlast v. To last longer than. 
outlaw n. A habitual lawbreaker. 
outlive v. To continue to exist after. 
out-of-the-way adj. Remotely situated. 
outpost n. A detachment of troops stationed at a distance from the main body to guard against surprise. 
outrage n. A gross infringement of morality or decency. 
outrageous adj. Shocking in conduct. 
outreach v. To reach or go beyond. 
outride v. To ride faster than. 
outrigger n. A part built or arranged to project beyond a natural outline for support. 
outright adv. Entirely. 
outskirt n. A border region. 
outstretch v. To extend. 
outstrip v. To go beyond. 
outweigh v. To surpass in importance or excellence. 
overdo v. To overtax the strength of. 
overdose n. An excessive dose, usually so large a dose of a medicine that its effect is toxic. 
overeat v. To eat to excess. 
overhang n. A portion of a structure which projects or hangs over. 
overleap v. To leap beyond. 
overlord n. One who holds supremacy over another. 
overpass v. To pass across or over, as a river. 
overpay v. To pay or reward in excess. 
overpower v. To gain supremacy or victory over by superior power. 
overproduction n. Excessive production. 
overreach v. To stretch out too far. 
overrun v. To infest or ravage. 
oversee v. To superintend. 
overseer n. A supervisor. 
overshadow v. To cast into the shade or render insignificant by comparison. 
overstride v. To step beyond. 
overthrow v. To vanquish an established ruler or government. 
overtone n. A harmonic. 
overture n. An instrumental prelude to an opera, oratorio, or ballet. 
overweight n. Preponderance. 
pacify v. To bring into a peaceful state. 
packet n. A bundle, as of letters. 
pact n. A covenant. 
pagan n. A worshiper of false gods. 
pageant n. A dramatic representation, especially a spectacular one. 
palate n. The roof of the mouth. 
palatial adj. Magnificent. 
paleontology n. The branch of biology that treats of ancient life and fossil organisms. 
palette n. A thin tablet, with a hole for the thumb, upon which artists lay their colors for painting. 
palinode n. A retraction. 
pall v. To make dull by satiety. 
palliate v. To cause to appear less guilty. 
pallid adj. Of a pale or wan appearance. 
palpable n. perceptible by feeling or touch. 
palsy n. Paralysis. 
paly adj. Lacking color or brilliancy. 
pamphlet n. A brief treatise or essay, usually on a subject of current interest. 
pamphleteer v. To compose or issue pamphlets, especially controversial ones. 
panacea n. A remedy or medicine proposed for or professing to cure all diseases. 
Pan-American adj. Including or pertaining to the whole of America, both North and South. 
pandemic adj. Affecting a whole people or all classes, as a disease. 
pandemonium n. A fiendish or riotous uproar. 
panegyric n. A formal and elaborate eulogy, written or spoken, of a person or of an act. 
panel n. A rectangular piece set in or as in a frame. 
panic n. A sudden, unreasonable, overpowering fear. 
panoply n. A full set of armor. 
panorama n. A series of large pictures representing a continuous scene. 
pantheism n. The worship of nature for itself or its beauty. 
Pantheon n. A circular temple at Rome with a fine Corinthian portico and a great domed roof. 
pantomime n. Sign-language. 
pantoscope n. A very wide-angled photographic lens. 
papacy n. The official head of the Roman Catholic Church. 
papyrus n. The writing-paper of the ancient Egyptians, and later of the Romans. 
parable n. A brief narrative founded on real scenes or events usually with a moral. 
paradox n. A statement or doctrine seemingly in contradiction to the received belief. 
paragon n. A model of excellence. 
parallel v. To cause to correspond or lie in the same direction and equidistant in all parts. 
parallelism n. Essential likeness. 
paralysis n. Loss of the power of contractility in the voluntary or involuntary muscles. 
paralyze v. To deprive of the power to act. 
paramount adj. Supreme in authority. 
paramour n. One who is unlawfully and immorally a lover or a mistress. 
paraphernalia n. Miscellaneous articles of equipment or adornment. 
paraphrase v. Translate freely. 
pare v. To cut, shave, or remove (the outside) from anything. 
parentage n. The relation of parent to child, of the producer to the produced, or of cause to effect. 
Pariah n. A member of a degraded class; a social outcast. 
parish n. The ecclesiastical district in charge of a pastor. 
Parisian adj. Of or pertaining to the city of Paris. 
parity n. Equality, as of condition or rank. 
parlance n. Mode of speech. 
parley v. To converse in. 
parliament n. A legislative body. 
parlor n. A room for reception of callers or entertainment of guests. 
parody v. To render ludicrous by imitating the language of. 
paronymous adj. Derived from the same root or primitive word. 
paroxysm n. A sudden outburst of any kind of activity. 
parricide n. The murder of a parent. 
parse v. To describe, as a sentence, by separating it into its elements and describing each word. 
parsimonious adj. Unduly sparing in the use or expenditure of money. 
partible adj. Separable. 
participant n. One having a share or part. 
participate v. To receive or have a part or share of. 
partition n. That which separates anything into distinct parts. 
partisan adj. Characterized by or exhibiting undue or unreasoning devotion to a party. 
passible adj. Capable of feeling of suffering. 
passive adj. Unresponsive. 
pastoral adj. Having the spirit or sentiment of rural life. 
paternal adj. Fatherly. 
paternity n. Fatherhood. 
pathos n. The quality in any form of representation that rouses emotion or sympathy. 
patriarch n. The chief of a tribe or race who rules by paternal right. 
patrician adj. Of senatorial or noble rank. 
patrimony n. An inheritance from an ancestor, especially from one’s father. 
patriotism n. Love and devotion to one’s country. 
patronize v. To exercise an arrogant condescension toward. 
patronymic adj. Formed after one’s father’s name. 
patter v. To mumble something over and over. 
paucity n. Fewness. 
pauper n. One without means of support. 
pauperism n. Dependence on charity. 
pavilion n. An open structure for temporary shelter. 
payee n. A person to whom money has been or is to be paid. 
peaceable adj. Tranquil. 
peaceful adj. Tranquil. 
peccable adj. Capable of sinning. 
peccadillo n. A small breach of propriety or principle. 
peccant adj. Guilty. 
pectoral adj. Pertaining to the breast or thorax. 
pecuniary adj. Consisting of money. 
pedagogics n. The science and art of teaching. 
pedagogue n. A schoolmaster. 
pedagogy n. The science and art of teaching 
pedal n. A lever for the foot usually applied only to musical instruments, cycles, and other machines. 
pedant n. A scholar who makes needless and inopportune display of his learning. 
peddle v. To go about with a small stock of goods to sell. 
pedestal n. A base or support as for a column, statue, or vase. 
pedestrian n. One who journeys on foot. 
pediatrics n. The department of medical science that relates to the treatment of diseases of childhood. 
pedigree n. One’s line of ancestors. 
peddler n. One who travels from house to house with an assortment of goods for retail. 
peerage n. The nobility. 
peerless adj. Of unequaled excellence or worth. 
peevish adj. Petulant. (irritable) 
pellucid adj. Translucent. 
penalty n. The consequences that follow the transgression of natural or divine law. 
penance n. Punishment to which one voluntarily submits or subjects himself as an expression of penitence. 
penchant n. A bias in favor of something. 
pendant n. Anything that hangs from something else, either for ornament or for use. 
pendulous adj. Hanging, especially so as to swing by an attached end or part. 
pendulum n. A weight hung on a rod, serving by its oscillation to regulate the rate of a clock. 
penetrable adj. That may be pierced by physical, moral, or intellectual force. 
penetrate v. To enter or force a way into the interior parts of. 
penetration n. Discernment. 
peninsular adj. Pertaining to a piece of land almost surrounded by water. 
penitence n. Sorrow for sin with desire to amend and to atone. 
penitential adj. Pertaining to sorrow for sin with desire to amend and to atone. 
pennant n. A small flag. 
pension n. A periodical allowance to an individual on account of past service done by him/her. 
pentagram n. A figure having five points or lobes. 
pentavalent adj. Quinqeuvalent. 
pentad n. The number five. 
pentagon n. A figure, especially, with five angles and five sides. 
pentahedron n. A solid bounded by five plane faces. 
pentameter n. In prosody, a line of verse containing five units or feet. 
pentathlon n. The contest of five associated exercises in the great games and the same contestants. 
penultimate adj. A syllable or member of a series that is last but one. 
penurious adj. Excessively sparing in the use of money. 
penury n. Indigence. 
perambulate v. To walk about. 
perceive v. To have knowledge of, or receive impressions concerning, through the medium of the body senses.
perceptible adj. Cognizable. 
perception n. Knowledge through the senses of the existence and properties of matter or the external world. 
percipience n. The act of perceiving. 
percipient n. One who or that which perceives. 
percolate v. To filter. 
percolator n. A filter. 
percussion n. The sharp striking of one body against another. 
peremptory adj. Precluding question or appeal. 
perennial adj. Continuing though the year or through many years. 
perfectible adj. Capable of being made perfect. 
perfidy n. Treachery. 
perforate v. To make a hole or holes through. 
perform v. To accomplish. 
perfumery n. The preparation of perfumes. 
perfunctory adj. Half-hearted. 
perhaps adv. Possibly. 
perigee n. The point in the orbit of the moon when it is nearest the earth. 
periodicity n. The habit or characteristic of recurrence at regular intervals. 
peripatetic adj. Walking about. 
perjure v. To swear falsely to. 
perjury n. A solemn assertion of a falsity. 
permanence n. A continuance in the same state, or without any change that destroys the essential form or nature.
permanent adj. Durable. 
permeate v. To pervade. 
permissible adj. That may be allowed. 
permutation n. Reciprocal change, different ordering of same items. 
pernicious adj. Tending to kill or hurt. 
perpendicular adj. Straight up and down. 
perpetrator n. The doer of a wrong or a criminal act. 
perpetuate v. To preserve from extinction or oblivion. 
perquisite n. Any profit from service beyond the amount fixed as salary or wages. 
persecution n. Harsh or malignant oppression. 
perseverance n. A persistence in purpose and effort. 
persevere v. To continue striving in spite of discouragements. 
persiflage n. Banter. 
persist v. To continue steadfast against opposition. 
persistence n. A fixed adherence to a resolve, course of conduct, or the like. 
personage n. A man or woman as an individual, especially one of rank or high station. 
personal adj. Not general or public. 
personality n. The attributes, taken collectively, that make up the character and nature of an individual. 
personnel n. The force of persons collectively employed in some service. 
perspective n. The relative importance of facts or matters from any special point of view. 
perspicacious adj. Astute. 
perspicacity n. Acuteness or discernment. 
perspicuous adj. Lucid. 
perspiration n. Sweat. 
perspire v. To excrete through the pores of the skin. 
persuade v. To win the mind of by argument, eloquence, evidence, or reflection. 
persuadable adj. capable of influencing to action by entreaty, statement, or anything that moves the feelings. 
pertinacious adj. Persistent or unyielding. 
pertinacity n. Unyielding adherence. 
pertinent adj. Relevant. 
perturb v. To disturb greatly. 
perturbation n. Mental excitement or confusion. 
perusal n. The act of reading carefully or thoughtfully. 
pervade v. To pass or spread through every part. 
pervasion n. The state of spreading through every part. 
pervasive adj. Thoroughly penetrating or permeating. 
perverse adj. Unreasonable. 
perversion n. Diversion from the true meaning or proper purpose. 
perversity n. Wickedness. 
pervert n. One who has forsaken a doctrine regarded as true for one esteemed false. 
pervious adj. Admitting the entrance or passage of another substance. 
pestilence n. A raging epidemic. 
pestilent adj. Having a malign influence or effect. 
pestilential adj. having the nature of or breeding pestilence. 
peter v. To fail or lose power, efficiency, or value. 
petrify v. To convert into a substance of stony hardness and character. 
petulance n. The character or condition of being impatient, capricious or petulant. 
petulant adj. Displaying impatience. 
pharmacopoeia n. A book containing the formulas and methods of preparation of medicines for the use of druggists.
pharmacy n. The art or business of compounding and dispensing medicines. 
phenomenal adj. Extraordinary or marvelous. 
phenomenon n. Any unusual occurrence. 
philander v. To play at courtship with a woman. 
philanthropic adj. Benevolent. 
philanthropist n. One who endeavors to help his fellow men. 
philanthropy n. Active humanitarianism. 
philately n. The study and collection of stamps.
philharmonic adj. Fond of music. 
philogynist n. One who is fond of women. 
philologist n. An expert in linguistics. 
philology n. The study of language in connection with history and literature. 
philosophize v. To seek ultimate causes and principles. 
philosophy n. The general principles, laws, or causes that furnish the rational explanation of anything. 
phlegmatic adj. Not easily roused to feeling or action. 
phonetic adj. Representing articulate sounds or speech. 
phonic adj. Pertaining to the nature of sound. 
phonogram n. A graphic character symbolizing an articulate sound. 
phonology n. The science of human vocal sounds. 
phosphorescence n. The property of emitting light. 
photoelectric adj. Pertaining to the combined action of light and electricity. 
photometer n. Any instrument for measuring the intensity of light or comparing the intensity of two lights. 
photometry n. The art of measuring the intensity of light. 
physicist n. A specialist in the science that treats of the phenomena associated with matter and energy. 
physics n. The science that treats of the phenomena associated with matter and energy. 
physiocracy n. The doctrine that land and its products are the only true wealth. 
physiognomy n. The external appearance merely. 
physiography n. Description of nature. 
physiology n. The science of organic functions. 
physique n. The physical structure or organization of a person. 
picayune adj. Of small value. 
piccolo n. A small flute. 
piece n. A loose or separated part, as distinguished from the whole or the mass. 
piecemeal adv. Gradually. 
pillage n. Open robbery, as in war. 
pillory n. A wooden framework in which an offender is fastened to boards and is exposed to public scorn.
pincers n. An instrument having two lever-handles and two jaws working on a pivot. 
pinchers n. An instrument having two jaws working on a pivot. 
pinnacle n. A high or topmost point, as a mountain-peak. 
pioneer n. One among the first to explore a country. 
pious adj. Religious. 
pique v. To excite a slight degree of anger in. 
piteous adj. Compassionate. 
pitiable adj. Contemptible. 
pitiful adj. Wretched. 
pitiless adj. Hard-hearted. 
pittance n. Any small portion or meager allowance. 
placate v. To bring from a state of angry or hostile feeling to one of patience or friendliness. 
placid adj. Serene. 
plagiarism n. The stealing of passages from the writings of another and publishing them as one’s own. 
planisphere n. A polar projection of the heavens on a chart. 
plasticity n. The property of some substances through which the form of the mass can readily be changed. 
platitude n. A written or spoken statement that is flat, dull, or commonplace. 
plaudit n. An expression of applause. 
plausible adj. Seeming likely to be true, though open to doubt. 
playful adj. Frolicsome. 
playwright n. A maker of plays for the stage. 
plea n. An argument to obtain some desired action. 
pleasant adj. Agreeable. 
pleasurable adj. Affording gratification. 
plebeian adj. Common. 
pledgee n. The person to whom anything is pledged. 
pledgeor n. One who gives a pledge. 
plenary adj. Entire. 
plenipotentiary n. A person fully empowered to transact any business. 
plenitude n. Abundance. 
plenteous adj. Abundant. 
plumb n. A weight suspended by a line to test the verticality of something. 
plummet n. A piece of lead for making soundings, adjusting walls to the vertical. 
pluperfect adj. Expressing past time or action prior to some other past time or action. 
plural adj. Containing or consisting of more than one. 
plurality n. A majority. 
plutocracy n. A wealthy class in a political community who control the government by means of their money. 
pneumatic adj. Pertaining to or consisting of air or gas. 
poesy n. Poetry. 
poetaster n. An inferior poet. 
poetic adj. Pertaining to poetry. 
poetics n. The rules and principles of poetry. 
poignancy n. Severity or acuteness, especially of pain or grief. 
poignant adj. Severely painful or acute to the spirit. 
poise n. Equilibrium. 
polar adj. Pertaining to the poles of a sphere, especially of the earth. 
polemics n. The art of controversy or disputation. 
pollen n. The fine dust-like grains or powder formed within the anther of a flowering plant. 
pollute v. To contaminate. 
polyarchy n. Government by several or many persons of what- ever class. 
polycracy n. The rule of many. 
polygamy n. the fact or condition of having more than one wife or husband at once. 
polyglot adj. Speaking several tongues. 
polygon n. A figure having many angles. 
polyhedron n. A solid bounded by plane faces, especially by more than four. 
polysyllable adj. Having several syllables, especially more than three syllables. 
polytechnic adj. Pertaining to, embracing, or practicing many arts. 
polytheism n. The doctrine or belief that there are more gods than one. 
pommel v. To beat with something thick or bulky. 
pomposity n. The quality of being marked by an assumed stateliness and impressiveness of manner. 
pompous adj. Marked by an assumed stateliness and impressiveness of manner. 
ponder v. To meditate or reflect upon. 
ponderous adj. Unusually weighty or forcible. 
pontiff n. The Pope. 
populace n. The common people. 
populous adj. Containing many inhabitants, especially in proportion to the territory. 
portend v. To indicate as being about to happen, especially by previous signs. 
portent n. Anything that indicates what is to happen. 
portfolio n. A portable case for holding writing-materials, drawings, etc. 
posit v. To present in an orderly manner. 
position n. The manner in which a thing is placed. 
positive adj. Free from doubt or hesitation. 
posse n. A force of men. 
possess v. To own. 
possession n. The having, holding, or detention of property in one’s power or command. 
possessive adj. Pertaining to the having, holding, or detention of property in one’s power or command. 
possessor n. One who owns, enjoys, or controls anything, as property. 
possible adj. Being not beyond the reach of power natural, moral, or supernatural. 
postdate v. To make the date of any writing later than the real date. 
posterior n. The hinder part. 
postgraduate adj. Pertaining to studies that are pursued after receiving a degree. 
postscript n. Something added to a letter after the writer’s signature. 
potency n. Power. 
potent adj. Physically powerful. 
potentate n. One possessed of great power or sway. 
potential n. Anything that may be possible. 
potion n. A dose of liquid medicine. 
powerless adj. Impotent. 
practicable adj. Feasible. 
prate v. To talk about vainly or foolishly. 
prattle v. To utter in simple or childish talk. 
preamble n. A statement introductory to and explanatory of what follows. 
precarious adj. Perilous. 
precaution n. A provision made in advance for some possible emergency or danger. 
precede v. To happen first. 
precedence n. Priority in place, time, or rank. 
precedent n. An instance that may serve as a guide or basis for a rule. 
precedential adj. Of the nature of an instance that may serve as a guide or basis for a rule. 
precession n. The act of going forward. 
precipice n. A high and very steep or approximately vertical cliff. 
precipitant adj. Moving onward quickly and heedlessly. 
precipitate v. To force forward prematurely. 
precise adj. Exact. 
precision n. Accuracy of limitation, definition, or adjustment. 
preclude v. To prevent. 
precocious adj. Having the mental faculties prematurely developed. 
precursor n. A forerunner or herald. 
predatory adj. Prone to pillaging. 
predecessor n. An incumbent of a given office previous to another. 
predicament n. A difficult, trying situation or plight. 
predicate v. To state as belonging to something. 
predict v. To foretell. 
prediction n. A prophecy. 
predominance n. Ascendancy or preponderance. 
predominant adj. Superior in power, influence, effectiveness, number, or degree. 
predominate v. To be chief in importance, quantity, or degree. 
preeminence n. Special eminence. 
preempt v. To secure the right of preference in the purchase of public land. 
preemption n. The right or act of purchasing before others. 
preengage v. To preoccupy. 
preestablish v. To settle or arrange beforehand. 
preexist v. To exist at a period or in a state earlier than something else. 
preexistence n. Existence antecedent to something. 
preface n. A brief explanation or address to the reader, at the beginning of a book. 
prefatory adj. Pertaining to a brief explanation to the reader at the beginning of a book. 
prefer v. To hold in higher estimation. 
preferable adj. More desirable than others. 
preference n. An object of favor or choice. 
preferential adj. Possessing, giving, or constituting preference or priority. 
preferment n. Preference. 
prefix v. To attach at the beginning. 
prehensible adj. Capable of being grasped. 
prehensile adj. Adapted for grasping or holding. 
prehension n. The act of laying hold of or grasping. 
prejudice n. A judgment or opinion formed without due examination of the facts. 
prelacy n. A system of church government. 
prelate n. One of a higher order of clergy having direct authority over other clergy. 
prelude n. An introductory or opening performance. 
premature adj. Coming too soon. 
premier adj. First in rank or position. 
premise n. A judgment as a conclusion. 
premonition n. Foreboding. 
preoccupation n. The state of having the mind, attention, or inclination preoccupied. 
preoccupy v. To fill the mind of a person to the exclusion of other subjects. 
preordain v. To foreordain. 
preparation n. An act or proceeding designed to bring about some event. 
preparatory adj. Having to do with what is preliminary. 
preponderant adj. Prevalent. 
preponderate v. To exceed in influence or power. 
prepossession n. A preconceived liking. 
preposterous adj. Utterly ridiculous or absurd. 
prerogative adj. Having superior rank or precedence. 
presage v. To foretell. 
prescience n. Knowledge of events before they take place. 
prescient adj. Foreknowing. 
prescript adj. Prescribed as a rule or model. 
prescriptible adj. Derived from authoritative direction. 
prescription n. An authoritative direction. 
presentient adj. Perceiving or feeling beforehand. 
presentiment n. Foreboding. 
presentment n. Semblance. 
preservation n. Conservation. 
presumption n. That which may be logically assumed to be true until disproved. 
presumptuous adj. Assuming too much. 
pretension n. A bold or presumptuous assertion. 
pretentious adj. Marked by pretense, conceit, or display. 
preternatural adj. Extraordinary. 
pretext n. A fictitious reason or motive. 
prevalence n. Frequency. 
prevalent adj. Of wide extent or frequent occurrence. 
prevaricate v. To use ambiguous or evasive language for the purpose of deceiving or diverting attention. 
prevention n. Thwarting. 
prickle v. To puncture slightly with fine, sharp points. 
priggish adj. Conceited. 
prim adj. Stiffly proper. 
prima adj. First. 
primer n. An elementary reading-book for children. 
primeval adj. Belonging to the first ages. 
primitive adj. Pertaining to the beginning or early times. 
principal adj. Most important. 
principality n. The territory of a reigning prince. 
principle n. A general truth or proposition. 
priory n. A monastic house. 
pristine adj. Primitive. 
privateer n. A vessel owned and officered by private persons, but carrying on maritime war. 
privilege n. A right or immunity not enjoyed by all, or that may be enjoyed only under special conditions. 
privity n. Knowledge shared with another or others regarding a private matter. 
privy adj. Participating with another or others in the knowledge of a secret transaction. 
probate adj. Relating to making proof, as of a will. 
probation n. Any proceeding designed to ascertain or test character, qualification, or the like. 
probe v. To search through and through. 
probity n. Virtue or integrity tested and confirmed. 
procedure n. A manner or method of acting. 
proceed v. To renew motion or action, as after rest or interruption. 
proclamation n. Any announcement made in a public manner. 
procrastinate v. To put off till tomorrow or till a future time. 
procrastination n. Delay. 
proctor n. An agent acting for another. 
prodigal n. One wasteful or extravagant, especially in the use of money or property. 
prodigious adj. Immense. 
prodigy n. A person or thing of very remarkable gifts or qualities. 
productive adj. Yielding in abundance. 
profession n. Any calling or occupation involving special mental or other special disciplines. 
professor n. A public teacher of the highest grade in a university or college. 
proffer v. To offer to another for acceptance. 
proficiency n. An advanced state of acquirement, as in some knowledge, art, or science. 
proficient adj. Possessing ample and ready knowledge or of skill in any art, science, or industry. 
profile n. An outline or contour. 
profiteer n. One who profits. 
profligacy n. Shameless viciousness. 
profligate adj. Abandoned to vice. 
profuse adj. Produced or displayed in overabundance. 
progeny n. Offspring. 
progression n. A moving forward or proceeding in course. 
prohibition n. A decree or an order forbidding something. 
prohibitionist n. One who favors the prohibition by law of the manufacture and sale of alcoholic beverages. 
prohibitory adj. Involving or equivalent to prohibition, especially of the sale of alcoholic beverages. 
projection n. A prominence. 
proletarian n. A person of the lowest or poorest class. 
prolific adj. Producing offspring or fruit. 
prolix adj. Verbose. 
prologue n. A prefatory statement or explanation to a poem, discourse, or performance. 
prolong v. To extend in time or duration. 
promenade v. To walk for amusement or exercise. 
prominence n. The quality of being noticeable or distinguished. 
prominent adj. Conspicuous in position, character, or importance. 
promiscuous adj. Brought together without order, distinction, or design (for sex). 
promissory adj. Expressing an engagement to pay. 
promontory n. A high point of land extending outward from the coastline into the sea. 
promoter n. A furtherer, forwarder, or encourager. 
promulgate v. To proclaim. 
propaganda n. Any institution or systematic scheme for propagating a doctrine or system. 
propagate v. To spread abroad or from person to person. 
propel v. To drive or urge forward. 
propellant adj. Propelling. 
propeller n. One who or that which propels. 
prophecy n. Any prediction or foretelling. 
prophesy v. To predict or foretell, especially under divine inspiration and guidance. 
propitious adj. Kindly disposed. 
proportionate adj. Being in proportion. 
propriety n. Accordance with recognized usage, custom, or principles. 
propulsion n. A driving onward or forward. 
prosaic adj. Unimaginative. 
proscenium n. That part of the stage between the curtain and the orchestra. 
proscribe v. To reject, as a teaching or a practice, with condemnation or denunciation. 
proscription n. Any act of condemnation and rejection from favor and privilege. 
proselyte n. One who has been won over from one religious belief to another. 
prosody n. The science of poetical forms. 
prospector n. One who makes exploration, search, or examination, especially for minerals. 
prospectus n. A paper or pamphlet containing information of a proposed undertaking. 
prostrate adj. Lying prone, or with the head to the ground. 
protagonist n. A leader in any enterprise or contest. 
protection n. Preservation from harm, danger, annoyance, or any other evil. 
protective adj. Sheltering. 
protector n. A defender. 
protege n. One specially cared for and favored by another usually older person. 
Protestant n. A Christian who denies the authority of the Pope and holds the right of special judgment. 
protomartyr n. The earliest victim in any cause. 
protocol n. A declaration or memorandum of agreement less solemn and formal than a treaty. 
protoplasm n. The substance that forms the principal portion of an animal or vegetable cell. 
prototype n. A work, original in character, afterward imitated in form or spirit. 
protract v. To prolong. 
protrude v. To push out or thrust forth. 
protrusion n. The act of protruding. 
protuberance n. Something that swells out from a surrounding surface. 
protuberant adj. Bulging. 
protuberate v. To swell or bulge beyond the surrounding surface. 
proverb n. A brief, pithy saying, condensing in witty or striking form the wisdom of experience. 
provident adj. Anticipating and making ready for future wants or emergencies. 
providential adj. Effected by divine guidance. 
provincial adj. Uncultured in thought and manner. 
proviso n. A clause in a contract, will, etc., by which its operation is rendered conditional. 
provocation n. An action or mode of conduct that excites resentment. 
prowess n. Strength, skill, and intrepidity in battle. 
proximately adv. Immediately. 
proxy n. A person who is empowered by another to represent him or her in a given matter. 
prudence n. Caution. 
prudential adj. Proceeding or marked by caution. 
prudery n. An undue display of modesty or delicacy. 
prurient adj. Inclined to lascivious thoughts and desires. 
pseudapostle n. A pretended or false apostle. 
pseudonym n. A fictitious name, especially when assumed by a writer. 
pseudonymity n. The state or character of using a fictitious name. 
psychiatry n. The branch of medicine that relates to mental disease. 
psychic adj. Pertaining to the mind or soul. 
psychopathic adj. Morally irresponsible. 
psychotherapy n. The treatment of mental disease. 
pudgy adj. Small and fat. 
puerile adj. Childish. 
pugnacious adj. Quarrelsome. 
puissant adj. Possessing strength. 
pulmonary adj. Pertaining to the lungs. 
punctilious adj. Strictly observant of the rules or forms prescribed by law or custom. 
punctual adj. Observant and exact in points of time. 
pungent adj. Affecting the sense of smell. 
pungency n. The quality of affecting the sense of smell. 
punitive adj. Pertaining to punishment. 
pupilage n. The state or period of being a student. 
purgatory n. An intermediate state where souls are made fit for paradise or heaven by expiatory suffering. 
purl v. To cause to whirl, as in an eddy. 
purloin v. To steal. 
purport n. Intent. 
purveyor n. one who supplies 
pusillanimous adj. Without spirit or bravery. 
putrescent adj. Undergoing decomposition of animal or vegetable matter accompanied by fetid odors. 
pyre n. A heap of combustibles arranged for burning a dead body. 
pyromania n. An insane propensity to set things on fire. 
pyrotechnic adj. Pertaining to fireworks or their manufacture. 
pyx n. A vessel or casket, usually of precious metal, in which the host is preserved. 
quackery n. Charlatanry 
quadrate v. To divide into quarters. 
quadruple v. To multiply by four. 
qualification n. A requisite for an employment, position, right, or privilege. 
qualify v. To endow or furnish with requisite ability, character, knowledge, skill, or possessions. 
qualm n. A fit of nausea. 
quandary n. A puzzling predicament. 
quantity n. Magnitude. 
quarantine n. The enforced isolation of any person or place infected with contagious disease. 
quarrelsome adj. Irascible. 
quarter n. One of four equal parts into which anything is or may be divided. 
quarterly adj. Occurring or made at intervals of three months. 
quartet n. A composition for four voices or four instruments. 
quarto n. An eight-page newspaper of any size. 
quay n. A wharf or artificial landing-place on the shore of a harbor or projecting into it. 
querulous adj. Habitually complaining. 
query v. To make inquiry. 
queue n. A file of persons waiting in order of their arrival, as for admittance. 
quibble n. An utterly trivial distinction or objection. 
quiescence n. Quiet. 
quiescent adj. Being in a state of repose or inaction. 
quiet adj. Making no noise. 
quietus n. A silencing, suppressing, or ending. 
quintessence n. The most essential part of anything. 
quintet n. Musical composition arranged for five voices or instruments. 
quite adv. Fully. 
Quixotic adj. Chivalrous or romantic to a ridiculous or extravagant degree. 
rabid adj. Affected with rabies or hydrophobia. 
racy adj. Exciting or exhilarating to the mind. 
radiance n. Brilliant or sparkling luster. 
radiate v. To extend in all directions, as from a source or focus. 
radical n. One who holds extreme views or advocates extreme measures. 
radix n. That from or on which something is developed. 
raillery n. Good-humored satire. 
ramify v. To divide or subdivide into branches or subdivisions. 
ramose adj. Branch-like. 
rampant adj. Growing, climbing, or running without check or restraint. 
rampart n. A bulwark or construction to oppose assault or hostile entry. 
rancor n. Malice. 
rankle v. To produce irritation or festering. 
rapacious adj. Disposed to seize by violence or by unlawful or greedy methods. 
rapid adj. Having great speed. 
rapine n. The act of seizing and carrying off property by superior force, as in war. 
rapt adj. Enraptured. 
raptorial adj. Seizing and devouring living prey. 
ration v. To provide with a fixed allowance or portion, especially of food. 
rationalism n. The formation of opinions by relying upon reason alone, independently of authority. 
raucous adj. Harsh. 
ravage v. To lay waste by pillage, rapine, devouring, or other destructive methods. 
ravenous adj. Furiously voracious or hungry. 
ravine n. A deep gorge or hollow, especially one worn by a stream or flow of water. 
reaction n. Tendency towards a former, or opposite state of things, as after reform, revolution, or inflation.
reactionary adj. Pertaining to, of the nature of, causing, or favoring reaction. 
readily adv. Without objection or reluctance. 
readjust v. To put in order after disarrangement. 
ready adj. In a state of preparedness for any given purpose or occasion. 
realism n. The principle and practice of depicting persons and scenes as they are believed really to exist. 
rearrange v. To arrange again or in a different order. 
reassure v. To give new confidence. 
rebellious adj. Insubordinate. 
rebuff n. A peremptory or unexpected rejection of advances or approaches. 
rebuild v. To build again or anew. 
rebut v. To oppose by argument or a sufficient answer. 
recant v. To withdraw formally one’s belief (in something previously believed or maintained). 
recapitulate v. To repeat again the principal points of. 
recapture v. To capture again. 
recede v. To move back or away. 
receivable adj. Capable of being or fit to be received – often money. 
receptive adj. Having the capacity, quality, or ability of receiving, as truths or impressions. 
recessive adj. Having a tendency to go back. 
recidivist n. A confirmed criminal. 
reciprocal adj. Mutually interchangeable or convertible. 
reciprocate v. To give and take mutually. 
reciprocity n. Equal mutual rights and benefits granted and enjoyed. 
recitation n. The act of reciting or repeating, especially in public and from memory. 
reck v. To have a care or thought for. 
reckless adj. Foolishly headless of danger. 
reclaim v. To demand or to obtain the return or restoration of. 
recline v. To cause to assume a leaning or recumbent attitude or position. 
recluse n. One who lives in retirement or seclusion. 
reclusory n. A hermitage. 
recognizance n. An acknowledgment entered into before a court with condition to do some particular act. 
recognize v. To recall the identity of (a person or thing). 
recoil v. To start back as in dismay, loathing, or dread. 
recollect v. To recall the knowledge of. 
reconcilable adj. Capable of being adjusted or harmonized. 
reconnoiter v. To make a preliminary examination of for military, surveying, or geological purposes. 
reconsider v. To review with care, especially with a view to a reversal of previous action. 
reconstruct v. To rebuild. 
recourse n. Resort to or application for help in exigency or trouble. 
recover v. To regain. 
recreant n. A cowardly or faithless person. 
recreate v. To refresh after labor. 
recrudescence n. The state of becoming raw or sore again. 
recrudescent adj. Becoming raw or sore again. 
recruit v. To enlist men for military or naval service. 
rectify v. To correct. 
rectitude n. The quality of being upright in principles and conduct. 
recuperate v. To recover. 
recur v. To happen again or repeatedly, especially at regular intervals. 
recure v. To cure again. 
recurrent adj. Returning from time to time, especially at regular or stated intervals. 
redemption n. The recovery of what is mortgaged or pledged, by paying the debt. 
redolent adj. Smelling sweet and agreeable. 
redolence n. Smelling sweet and agreeable. 
redoubtable adj. Formidable. 
redound n. Rebound. 
redress v. To set right, as a wrong by compensation or the punishment of the wrong-doer. 
reducible adj. That may be reduced. 
redundance n. Excess. 
redundant adj. Constituting an excess. 
reestablish v. To restore. 
refer v. To direct or send for information or other purpose. 
referrer n. One who refers. 
referable adj. Ascribable. 
referee n. An umpire. 
refinery n. A place where some crude material, as sugar or petroleum, is purified. 
reflectible adj. Capable of being turned back. 
reflection n. The throwing off or back of light, heat, sound, or any form of energy that travels in waves. 
reflector n. A mirror, as of metal, for reflecting light, heat, or sound in a particular direction. 
reflexible adj. Capable of being reflected. 
reform n. Change for the better. 
reformer n. One who carries out a reform. 
refract v. To bend or turn from a direct course. 
refractory adj. Not amenable to control. 
refragable adj. Capable of being refuted. 
refringency n. Power to refract. 
refringent adj. Having the power to refract. 
refusal n. Denial of what is asked. 
refute v. To prove to be wrong. 
regale v. To give unusual pleasure. 
regalia n. pl. The emblems of royalty. 
regality n. Royalty. 
regenerate v. To reproduce. 
regent n. One who is lawfully deputized to administer the government for the time being in the name of the ruler.
regicide n. The killing of a king or sovereign. 
regime n. Particular conduct or administration of affairs. 
regimen n. A systematized order or course of living with reference to food, clothing and personal habits. 
regiment n. A body of soldiers. 
regnant adj. Exercising royal authority in one’s own right. 
regress v. To return to a former place or condition. 
regretful adj. Feeling, expressive of, or full of regret. 
rehabilitate v. To restore to a former status, capacity, right rank, or privilege. 
reign v. To hold and exercise sovereign power. 
reimburse v. To pay back as an equivalent of what has been expended. 
rein n. A step attached to the bit for controlling a horse or other draft-animal. 
reinstate v. To restore to a former state, station, or authority. 
reiterate v. To say or do again and again. 
rejoin v. To reunite after separation. 
rejuvenate v. To restore to youth. 
rejuvenescence n. A renewal of youth. 
relapse v. To suffer a return of a disease after partial recovery. 
relegate v. To send off or consign, as to an obscure position or remote destination. 
relent v. To yield. 
relevant adj. Bearing upon the matter in hand. 
reliance n. Dependence. 
reliant adj. Having confidence. 
relinquish v. To give up using or having. 
reliquary n. A casket, coffer, or repository in which relics are kept. 
relish v. To like the taste or savor of. 
reluctance n. Unwillingness. 
reluctant adj. Unwilling. 
remembrance n. Recollection. 
reminiscence n. The calling to mind of incidents within the range of personal knowledge or experience. 
reminiscent adj. Pertaining to the recollection of matters of personal interest. 
remiss adj. Negligent. 
remission n. Temporary diminution of a disease. 
remodel v. Reconstruct. 
remonstrance n. Reproof. 
remonstrant adj. Having the character of a reproof. 
remonstrate v. To present a verbal or written protest to those who have power to right or prevent a wrong. 
remunerate v. To pay or pay for. 
remuneration n. Compensation. 
Renaissance n. The revival of letters, and then of art, which marks the transition from medieval to modern time.
rendezvous n. A prearranged place of meeting. 
rendition n. Interpretation. 
renovate v. To restore after deterioration, as a building. 
renunciation n. An explicit disclaimer of a right or privilege. 
reorganize v. To change to a more satisfactory form of organization. 
reparable adj. Capable of repair. 
reparation n. The act of making amends, as for an injury, loss, or wrong. 
repartee n. A ready, witty, or apt reply. 
repeal v. To render of no further effect. 
repel v. To force or keep back in a manner, physically or mentally. 
repellent adj. Having power to force back in a manner, physically or mentally. 
repentance n. Sorrow for something done or left undone, with desire to make things right by undoing the wrong. 
repertory n. A place where things are stored or gathered together. 
repetition n. The act of repeating. 
repine v. To indulge in fretfulness and faultfinding. 
replenish v. To fill again, as something that has been emptied. 
replete adj. Full to the uttermost. 
replica n. A duplicate executed by the artist himself, and regarded, equally with the first, as an original. 
repository n. A place in which goods are stored. 
reprehend v. To find fault with. 
reprehensible adj. Censurable. 
reprehension n. Expression of blame. 
repress v. To keep under restraint or control. 
repressible adj. Able to be kept under restraint or control. 
reprieve v. To grant a respite from punishment to. 
reprimand v. To chide or rebuke for a fault. 
reprisal n. Any infliction or act by way of retaliation on an enemy. 
reprobate n. One abandoned to depravity and sin. 
reproduce v. To make a copy of. 
reproduction n. The process by which an animal or plant gives rise to another of its kind. 
reproof n. An expression of disapproval or blame personally addressed to one censured. 
repudiate v. To refuse to have anything to do with. 
repugnance n. Thorough dislike. 
repugnant adj. Offensive to taste and feeling. 
repulse n. The act of beating or driving back, as an attacking or advancing enemy. 
repulsive adj. Grossly offensive. 
repute v. To hold in general opinion. 
requiem n. A solemn mass sung for the repose of the souls of the dead. 
requisite adj. Necessary. 
requital n. Adequate return for good or ill. 
requite v. To repay either good or evil to, as to a person. 
rescind v. To make void, as an act, by the enacting authority or a superior authority. 
reseat v. To place in position of office again. 
resemblance n. Similarity in quality or form. 
resent v. To be indignant at, as an injury or insult. 
reservoir n. A receptacle where a quantity of some material, especially of a liquid or gas, may be kept. 
residue n. A remainder or surplus after a part has been separated or otherwise treated. 
resilience n. The power of springing back to a former position 
resilient adj. Having the quality of springing back to a former position. 
resistance n. The exertion of opposite effort or effect. 
resistant adj. Offering or tending to produce resistance. 
resistive adj. Having or exercising the power of resistance. 
resistless adj. Powerless. 
resonance n. The quality of being able to reinforce sound by sympathetic vibrations. 
resonance adj. Able to reinforce sound by sympathetic vibrations. 
resonate v. To have or produce resonance. 
resource n. That which is restored to, relied upon, or made available for aid or support. 
respite n. Interval of rest. 
resplendent adj. Very bright. 
respondent adj. Answering. 
restitution n. Restoration of anything to the one to whom it properly belongs. 
resumption n. The act of taking back, or taking again. 
resurgent adj. Surging back or again. 
resurrection n. A return from death to life 
resuscitate v. To restore from apparent death. 
retaliate v. To repay evil with a similar evil. 
retch v. To make an effort to vomit. 
retention n. The keeping of a thing within one’s power or possession. 
reticence n. The quality of habitually keeping silent or being reserved in utterance. 
reticent adj. Habitually keeping silent or being reserved in utterance. 
retinue n. The body of persons who attend a person of importance in travel or public appearance. 
retort n. A retaliatory speech. 
retouch v. To modify the details of. 
retrace v. To follow backward or toward the place of beginning, as a track or marking. 
retract v. To recall or take back (something that one has said). 
retrench v. To cut down or reduce in extent or quantity. 
retrieve v. To recover something by searching. 
retroactive adj. Operative on, affecting, or having reference to past events, transactions, responsibilities. 
retrograde v. To cause to deteriorate or to move backward. 
retrogression n. A going or moving backward or in a reverse direction. 
retrospect n. A view or contemplation of something past. 
retrospective adj. Looking back on the past. 
reunite v. To unite or join again, as after separation. 
revelation n. A disclosing, discovering, or making known of what was before secret, private, or unknown. 
revere v. To regard with worshipful veneration. 
reverent adj. Humble. 
reversion n. A return to or toward some former state or condition. 
revert v. To return, or turn or look back, as toward a former position or the like. 
revile v. To heap approach or abuse upon. 
revisal n. Revision. 
revise v. To examine for the correction of errors, or for the purpose of making changes. 
revocation n. Repeal. 
revoke v. To rescind. 
rhapsody n. Rapt or rapturous utterance. 
rhetoric n. The art of discourse. 
rhetorician n. A showy writer or speaker. 
ribald adj. Indulging in or manifesting coarse indecency or obscenity. 
riddance n. The act or ridding or delivering from something undesirable. 
ridicule n. Looks or acts expressing amused contempt. 
ridiculous adj. Laughable and contemptible. 
rife adj. Abundant. 
righteousness n. Rectitude. 
rightful adj. Conformed to a just claim according to established laws or usage. 
rigmarole n. Nonsense. 
rigor n. Inflexibility. 
rigorous adj. Uncompromising. 
ripplet n. A small ripple, as of water. 
risible adj. capable of exciting laughter. 
rivulet n. A small stream or brook. 
robust adj. Characterized by great strength or power of endurance. 
rondo n. A musical composition during which the first part or subject is repeated several times. 
rookery n. A place where crows congregate to breed. 
rotary adj. Turning around its axis, like a wheel, or so constructed as to turn thus. 
rotate v. To cause to turn on or as on its axis, as a wheel. 
rote n. Repetition of words or sounds as a means of learning them, with slight attention. 
rotund adj. Round from fullness or plumpness. 
rudimentary adj. Being in an initial, early, or incomplete stage of development. 
rue v. To regret extremely. 
ruffian adj. A lawless or recklessly brutal fellow. 
ruminant adj. Chewing the cud. 
ruminate v. To chew over again, as food previously swallowed and regurgitated. 
rupture v. To separate the parts of by violence. 
rustic adj. Characteristic of dwelling in the country. 
ruth n. Sorrow for another’s misery. 
sacrifice v. To make an offering of to deity, especially by presenting on an altar. 
sacrificial adj. Offering or offered as an atonement for sin. 
sacrilege n. The act of violating or profaning anything sacred. 
sacrilegious adj. Impious. 
safeguard v. To protect. 
sagacious adj. Able to discern and distinguish with wise perception. 
salacious adj. Having strong sexual desires. 
salience n. The condition of standing out distinctly. 
salient adj. Standing out prominently. 
saline adj. Constituting or consisting of salt. 
salutary adj. Beneficial. 
salutation n. Any form of greeting, hailing, or welcome, whether by word or act. 
salutatory n. The opening oration at the commencement in American colleges. 
salvage n. Any act of saving property. 
salvo n. A salute given by firing all the guns, as at the funeral of an officer. 
sanctimonious adj. Making an ostentatious display or hypocritical pretense of holiness or piety. 
sanction v. To approve authoritatively. 
sanctity n. Holiness. 
sanguinary adj. Bloody. 
sanguine adj. Having the color of blood. 
sanguineous adj. Consisting of blood. 
sapid adj. Affecting the sense of taste. 
sapience n. Deep wisdom or knowledge. 
sapient adj. Possessing wisdom. 
sapiential adj. Possessing wisdom. 
saponaceous adj. Having the nature or quality of soap. 
sarcasm n. Cutting and reproachful language. 
sarcophagus n. A stone coffin or a chest-like tomb. 
sardonic adj. Scornfully or bitterly sarcastic. 
satiate v. To satisfy fully the appetite or desire of. 
satire n. The employment of sarcasm, irony, or keenness of wit in ridiculing vices. 
satiric adj. Resembling poetry, in which vice, incapacity ,or corruption is held up to ridicule. 
satirize v. To treat with sarcasm or derisive wit. 
satyr n. A very lascivious person. 
savage n. A wild and uncivilized human being. 
savor v. To perceive by taste or smell. 
scabbard n. The sheath of a sword or similar bladed weapon. 
scarcity n. Insufficiency of supply for needs or ordinary demands. 
scholarly adj. Characteristic of an erudite person. 
scholastic adj. Pertaining to education or schools. 
scintilla n. The faintest ray. 
scintillate v. To emit or send forth sparks or little flashes of light. 
scope n. A range of action or view. 
scoundrel n. A man without principle. 
scribble n. Hasty, careless writing. 
scribe n. One who writes or is skilled in writing. 
script n. Writing or handwriting of the ordinary cursive form. 
Scriptural adj. Pertaining to, contained in, or warranted by the Holy Scriptures. 
scruple n. Doubt or uncertainty regarding a question of moral right or duty. 
scrupulous adj. Cautious in action for fear of doing wrong. 
scurrilous adj. Grossly indecent or vulgar. 
scuttle v. To sink (a ship) by making holes in the bottom. 
scythe n. A long curved blade for mowing, reaping, etc. 
seance n. A meeting of spirituals for consulting spirits. 
sear v. To burn on the surface. 
sebaceous adj. Pertaining to or appearing like fat. 
secant adj. Cutting, especially into two parts. 
secede v. To withdraw from union or association, especially from a political or religious body. 
secession n. Voluntary withdrawal from fellowship, especially from political or religious bodies. 
seclude v. To place, keep, or withdraw from the companionship of others. 
seclusion n. Solitude. 
secondary adj. Less important or effective than that which is primary. 
secondly adv. In the second place in order or succession. 
second-rate adj. Second in quality, size, rank, importance, etc. 
secrecy n. Concealment. 
secretary n. One who attends to correspondence, keeps records. or does other writing for others. 
secretive adj. Having a tendency to conceal. 
sedate adj. Even-tempered. 
sedentary adj. Involving or requiring much sitting. 
sediment n. Matter that settles to the bottom of a liquid. 
sedition n. Conduct directed against public order and the tranquillity of the state. 
seditious adj. Promotive of conduct directed against public order and the tranquillity of the state. 
seduce v. To entice to surrender chastity. 
sedulous adj. Persevering in effort or endeavor. 
seer n. A prophet. 
seethe v. To be violently excited or agitated. 
seignior n. A title of honor or respectful address, equivalent to sir. 
seismograph n. An instrument for recording the phenomena of earthquakes. 
seize v. To catch or take hold of suddenly and forcibly. 
selective adj. Having the power of choice. 
self-respect n. Rational self-esteem. 
semblance n. Outward appearance. 
semicivilized adj. Half-civilized. 
semiconscious adj. Partially conscious. 
semiannual adj. Recurring at intervals of six months. 
semicircle n. A half-circle. 
seminar n. Any assemblage of pupils for real research in some specific study under a teacher. 
seminary n. A special school, as of theology or pedagogics. 
senile adj. Peculiar to or proceeding from the weakness or infirmity of old age. 
sensation n. A condition of mind resulting from spiritual or inherent feeling. 
sense n. The signification conveyed by some word, phrase, or action. 
sensibility n. Power to perceive or feel. 
sensitive adj. Easily affected by outside operations or influences. 
sensorium n. The sensory apparatus. 
sensual adj. Pertaining to the body or the physical senses. 
sensuous adj. Having a warm appreciation of the beautiful or of the refinements of luxury. 
sentence n. A related group of words containing a subject and a predicate and expressing a complete thought.
sentience n. Capacity for sensation or sense-perception. 
sentient adj. Possessing the power of sense or sense-perception. 
sentinel n. Any guard or watch stationed for protection. 
separable adj. Capable of being disjoined or divided. 
separate v. To take apart. 
separatist n. A seceder. 
septennial adj. Recurring every seven years. 
sepulcher n. A burial-place. 
sequacious adj. Ready to be led. 
sequel n. That which follows in consequence of what has previously happened. 
sequence n. The order in which a number or persons, things, or events follow one another in space or time. 
sequent adj. Following in the order of time. 
sequester v. To cause to withdraw or retire, as from society or public life. 
sequestrate v. To confiscate. 
sergeant n. A non-commissioned military officer ranking next above a corporal. 
sergeant-at-arms n. An executive officer in legislative bodies who enforces the orders of the presiding officer. 
sergeant-major n. The highest non-commissioned officer in a regiment. 
service n. Any work done for the benefit of another. 
serviceable adj. Durable. 
servitude n. Slavery. 
severance n. Separation. 
severely adv. Extremely. 
sextet n. A band of six singers or players. 
sextuple adj. Multiplied by six. 
sheer adj. Absolute. 
shiftless adj. Wanting in resource, energy, or executive ability. 
shrewd adj. Characterized by skill at understanding and profiting by circumstances. 
shriek n. A sharp, shrill outcry or scream, caused by agony or terror. 
shrinkage n. A contraction of any material into less bulk or dimension. 
shrivel v. To draw or be drawn into wrinkles. 
shuffle n. A mixing or changing the order of things. 
sibilance n. A hissing sound. 
sibilant adj. Made with a hissing sound. 
sibilate v. To give a hissing sound to, as in pronouncing the letter s. 
sidelong adj. Inclining or tending to one side. 
sidereal adj. Pertaining to stars or constellations. 
siege n. A beleaguerment. 
significance n. Importance. 
significant adj. Important, especially as pointing something out. 
signification n. The meaning conveyed by language, actions, or signs. 
similar adj. Bearing resemblance to one another or to something else. 
simile n. A comparison which directs the mind to the representative object itself. 
similitude n. Similarity. 
simplify v. To make less complex or difficult. 
simulate v. Imitate. 
simultaneous adj. Occurring, done, or existing at the same time. 
sinecure n. Any position having emoluments with few or no duties. 
singe v. To burn slightly or superficially. 
sinister adj. Evil. 
sinuosity n. The quality of curving in and out. 
sinuous adj. Curving in and out. 
sinus n. An opening or cavity. 
siren n. A sea-nymph, described by Homer as dwelling between the island of Circe and Scylla. 
sirocco n. hot winds from Africa. 
sisterhood n. A body of sisters united by some bond of sympathy or by a religious vow. 
skeptic n. One who doubts any statements. 
skepticism n. The entertainment of doubt concerning something. 
skiff n. Usually, a small light boat propelled by oars. 
skirmish n. Desultory fighting between advanced detachments of two armies. 
sleight n. A trick or feat so deftly done that the manner of performance escapes observation. 
slight adj. Of a small importance or significance. 
slothful adj. Lazy. 
sluggard n. A person habitually lazy or idle. 
sociable adj. Inclined to seek company. 
socialism n. A theory of civil polity that aims to secure the reconstruction of society. 
socialist adj. One who advocates reconstruction of society by collective ownership of land and capital. 
sociology n. The philosophical study of society. 
Sol n. The sun. 
solace n. Comfort in grief, trouble, or calamity. 
solar adj. Pertaining to the sun. 
solder n. A fusible alloy used for joining metallic surfaces or margins. 
soldier n. A person engaged in military service. 
solecism n. Any violation of established rules or customs. 
solicitor n. One who represents a client in court of justice; an attorney. 
solicitude n. Uneasiness of mind occasioned by desire, anxiety, or fear. 
soliloquy n. A monologue. 
solstice n. The time of year when the sun is at its greatest declination. 
soluble adj. Capable of being dissolved, as in a fluid. 
solvent adj. Having sufficient funds to pay all debts. 
somber adj. Gloomy. 
somniferous adj. Tending to produce sleep. 
somnolence n. Oppressive drowsiness. 
somnolent adj. Sleepy. 
sonata n. An instrumental composition. 
sonnet n. A poem of fourteen decasyllabic or octosyllabiclines expressing two successive phrases. 
sonorous adj. Resonant. 
soothsayer n. One who claims to have supernatural insight or foresight. 
sophism n. A false argument understood to be such by the reasoner himself and intentionally used to deceive
sophistical adj. Fallacious. 
sophisticate v. To deprive of simplicity of mind or manner. 
sophistry n. Reasoning sound in appearance only, especially when designedly deceptive. 
soprano n. A woman’s or boy’s voice of high range. 
sorcery n. Witchcraft. 
sordid adj. Of degraded character or nature. 
souvenir n. A token of remembrance. 
sparse adj. Thinly diffused. 
Spartan adj. Exceptionally brave; rigorously severe. 
spasmodic adj. Convulsive. 
specialize v. To assume an individual or specific character, or adopt a singular or special course. 
specialty n. An employment limited to one particular line of work. 
specie n. A coin or coins of gold, silver, copper, or other metal. 
species n. A classificatory group of animals or plants subordinate to a genus. 
specimen n. One of a class of persons or things regarded as representative of the class. 
specious adj. Plausible. 
spectator n. One who beholds or looks on. 
specter n. Apparition. 
spectrum n. An image formed by rays of light or other radiant energy. 
speculate v. To pursue inquiries and form conjectures. 
speculator n. One who makes an investment that involves a risk of loss, but also a chance of profit. 
sphericity n. The state or condition of being a sphere. 
spheroid n. A body having nearly the form of a sphere. 
spherometer n. An instrument for measuring curvature or radii of spherical surfaces. 
spinous adj. Having spines. 
spinster n. A woman who has never been married. 
spontaneous adj. Arising from inherent qualities or tendencies without external efficient cause. 
sprightly adj. Vivacious. 
spurious adj. Not genuine. 
squabble v. To quarrel. 
squalid adj. Having a dirty, mean, poverty-stricken appearance. 
squatter n. One who settles on land without permission or right. 
stagnant adj. Not flowing: said of water, as in a pool. 
stagnate v. To become dull or inert. 
stagnation n. The condition of not flowing or not changing. 
stagy adj. Having a theatrical manner. 
staid adj. Of a steady and sober character. 
stallion n. An uncastrated male horse, commonly one kept for breeding. 
stanchion n. A vertical bar, or a pair of bars, used to confine cattle in a stall. 
stanza n. A group of rimed lines, usually forming one of a series of similar divisions in a poem. 
statecraft n. The art of conducting state affairs. 
static adj. Pertaining to or designating bodies at rest or forces in equilibrium. 
statics n. The branch of mechanics that treats of the relations that subsist among forces in order. 
stationary adj. Not moving. 
statistician n. One who is skilled in collecting and tabulating numerical facts. 
statuesque adj. Having the grace, pose, or quietude of a statue. 
statuette n. A figurine. 
stature n. The natural height of an animal body. 
statute n. Any authoritatively declared rule, ordinance, decree, or law. 
stealth n. A concealed manner of acting. 
stellar adj. Pertaining to the stars. 
steppe n. One of the extensive plains in Russia and Siberia. 
sterling adj. Genuine. 
stifle v. To smother. 
stigma n. A mark of infamy or token of disgrace attaching to a person as the result of evil-doing. 
stiletto n. A small dagger. 
stimulant n. Anything that rouses to activity or to quickened action. 
stimulate v. To rouse to activity or to quickened action. 
stimulus n. Incentive. 
stingy adj. Cheap, unwilling to spend money. 
stipend n. A definite amount paid at stated periods in compensation for services or as an allowance. 
Stoicism n. The principles or the practice of the Stoics-being very even tempered in success and failure. 
stolid adj. Expressing no power of feeling or perceiving. 
strait n. A narrow passage of water connecting two larger bodies of water. 
stratagem n. Any clever trick or device for obtaining an advantage. 
stratum n. A natural or artificial layer, bed, or thickness of any substance or material. 
streamlet n. Rivulet. 
stringency n. Strictness. 
stringent adj. Rigid. 
stripling n. A mere youth. 
studious adj. Having or showing devotion to the acquisition of knowledge. 
stultify v. To give an appearance of foolishness to. 
stupendous adj. Of prodigious size, bulk, or degree. 
stupor n. Profound lethargy. 
suasion n. The act of persuading. 
suave adj. Smooth and pleasant in manner. 
subacid adj. Somewhat sharp or biting. 
subaquatic adj. Being, formed, or operating under water. 
subconscious adj. Being or occurring in the mind, but without attendant consciousness or conscious perception. 
subjacent adj. Situated directly underneath. 
subjection n. The act of bringing into a state of submission. 
subjugate v. To conquer. 
subliminal adj. Being beneath the threshold of consciousness. 
sublingual adj. Situated beneath the tongue. 
submarine adj. Existing, done, or operating beneath the surface of the sea. 
submerge v. To place or plunge under water. 
submergence n. The act of submerging. 
submersible adj. Capable of being put underwater. 
submersion n. The act of submerging. 
submission n. A yielding to the power or authority of another. 
submittal n. The act of submitting. 
subordinate adj. Belonging to an inferior order in a classification. 
subsequent adj. Following in time. 
subservience n. The quality, character, or condition of being servilely following another’s behests. 
subservient adj. Servilely following another’s behests. 
subside v. To relapse into a state of repose and tranquillity. 
subsist v. To be maintained or sustained. 
subsistence n. Sustenance. 
substantive adj. Solid. 
subtend v. To extend opposite to. 
subterfuge n. Evasion. 
subterranean adj. Situated or occurring below the surface of the earth. 
subtle adj. Discriminating. 
subtrahend n. That which is to be subtracted. 
subversion n. An overthrow, as from the foundation. 
subvert v. To bring to ruin. 
succeed v. To accomplish what is attempted or intended. 
success n. A favorable or prosperous course or termination of anything attempted. 
successful adj. Having reached a high degree of worldly prosperity. 
successor n. One who or that which takes the place of a predecessor or preceding thing. 
succinct adj. Concise. 
succulent adj. Juicy. 
succumb v. To cease to resist. 
sufferance n. Toleration. 
sufficiency n. An ample or adequate supply. 
suffrage n. The right or privilege of voting. 
suffuse v. To cover or fill the surface of. 
suggestible adj. That can be suggested. 
suggestive adj. Stimulating to thought or reflection. 
summary n. An abstract. 
sumptuous adj. Rich and costly. 
superabundance n. An excessive amount. 
superadd v. To add in addition to what has been added. 
superannuate v. To become deteriorated or incapacitated by long service. 
superb adj. Sumptuously elegant. 
supercilious adj. Exhibiting haughty and careless contempt. 
superficial adj. Knowing and understanding only the ordinary and the obvious. 
superfluity n. That part of anything that is in excess of what is needed. 
superfluous adj. Being more than is needed. 
superheat v. To heat to excess. 
superintend v. To have the charge and direction of, especially of some work or movement. 
superintendence n. Direction and management. 
superintendent n. One who has the charge and direction of, especially of some work or movement. 
superlative n. That which is of the highest possible excellence or eminence. 
supernatural adj. Caused miraculously or by the immediate exercise of divine power. 
supernumerary adj. Superfluous. 
supersede v. To displace. 
supine adj. Lying on the back. 
supplant v. To take the place of. 
supple adj. Easily bent. 
supplementary adj. Being an addition to. 
supplicant n. One who asks humbly and earnestly. 
supplicate v. To beg. 
supposition n. Conjecture. 
suppress v. To prevent from being disclosed or punished. 
suppressible adj. Capable of being suppressed. 
suppression n. A forcible putting or keeping down. 
supramundane adj. Supernatural. 
surcharge n. An additional amount charged. 
surety n. Security for payment or performance. 
surfeit v. To feed to fullness or to satiety. 
surmise v. To conjecture. 
surmount v. To overcome by force of will. 
surreptitious adj. Clandestine. 
surrogate n. One who or that which is substituted for or appointed to act in place of another. 
surround v. To encircle. 
surveyor n. A land-measurer. 
susceptibility n. A specific capability of feeling or emotion. 
susceptible adj. Easily under a specified power or influence. 
suspense n. Uncertainty. 
suspension n. A hanging from a support. 
suspicious adj. Inclined to doubt or mistrust. 
sustenance n. Food. 
swarthy adj. Having a dark hue, especially a dark or sunburned complexion. 
Sybarite n. A luxurious person. 
sycophant n. A servile flatterer, especially of those in authority or influence. 
syllabic adj. Consisting of that which is uttered in a single vocal impulse. 
syllabication n. Division of words into that which is uttered in a single vocal impulse. 
syllable n. That which is uttered in a single vocal impulse. 
syllabus n. Outline of a subject, course, lecture, or treatise. 
sylph n. A slender, graceful young woman or girl. 
symmetrical adj. Well-balanced. 
symmetry n. Relative proportion and harmony. 
sympathetic adj. Having a fellow-feeling for or like feelings with another or others. 
sympathize v. To share the sentiments or mental states of another. 
symphonic adj. Characterized by a harmonious or agreeable mingling of sounds. 
symphonious adj. Marked by a harmonious or agreeable mingling of sounds. 
symphony n. A harmonious or agreeable mingling of sounds. 
synchronism n. Simultaneousness. 
syndicate n. An association of individuals united for the prosecution of some enterprise. 
syneresis n. The coalescence of two vowels or syllables, as e’er for ever. 
synod n. An ecclesiastical council. 
synonym n. A word having the same or almost the same meaning as some other. 
synopsis n. A syllabus or summary. 
systematic adj. Methodical. 
tableau n. An arrangement of inanimate figures representing a scene from real life. 
tacit adj. Understood. 
taciturn adj. Disinclined to conversation. 
tack n. A small sharp-pointed nail. 
tact n. Fine or ready mental discernment shown in saying or doing the proper thing. 
tactician n. One who directs affairs with skill and shrewdness. 
tactics n. Any maneuvering or adroit management for effecting an object. 
tangency n. The state of touching. 
tangent adj. Touching. 
tangible adj. Perceptible by touch. 
tannery n. A place where leather is tanned. 
tantalize v. To tease. 
tantamount adj. Having equal or equivalent value, effect, or import. 
tapestry n. A fabric to which a pattern is applied with a needle, designed for ornamental hangings. 
tarnish v. To lessen or destroy the luster of in any way. 
taut adj. Stretched tight. 
taxation n. A levy, by government, of a fixed contribution. 
taxidermy n. The art or process of preserving dead animals or parts of them. 
technic adj. Technical. 
technicality n. Something peculiar to a particular art, trade, or the like. 
technique n. Manner of performance. 
technography n. The scientific description or study of human arts and industries in their historic development.
technology n. The knowledge relating to industries and manufactures. 
teem v. To be full to overflowing. 
telepathy n. Thought-transference. 
telephony n. The art or process of communicating by telephone. 
telescope v. To drive together so that one slides into the another like the sections of a spy-glass. 
telltale adj. That gives warning or information. 
temerity n. Recklessness. 
temporal adj. Pertaining to or concerned with the affairs of the present life. 
temporary adj. Lasting for a short time only. 
temporize v. To pursue a policy of delay. 
tempt v. To offer to (somebody) an inducement to do wrong. 
tempter n. An allurer or enticer to evil. 
tenacious adj. Unyielding. 
tenant n. An occupant. 
tendency n. Direction or inclination, as toward some objector end. 
tenet n. Any opinion, principle, dogma, or doctrine that a person believes or maintains as true. 
tenor n. A settled course or manner of progress. 
tense adj. Strained to stiffness. 
tentative adj. Done as an experiment. 
tenure n. The term during which a thing is held. 
tercentenary adj. Pertaining to a period of 300 years. 
termagant adj. Violently abusive and quarrelsome. 
terminal adj. Pertaining to or creative of a boundary, limit. 
terminate v. To put an end or stop to. 
termination n. The act of ending or concluding. 
terminus n. The final point or goal. 
terrify v. To fill with extreme fear. 
territorial adj. Pertaining to the domain over which a sovereign state exercises jurisdiction. 
terse adj. Pithy. 
testament n. A will. 
testator n. The maker of a will. 
testimonial n. A formal token of regard, often presented in public. 
thearchy n. Government by a supreme deity. 
theism n. Belief in God. 
theocracy n. A government administered by ecclesiastics. 
theocrasy n. The mixed worship of polytheism. 
theologian n. A professor of divinity. 
theological adj. Based on or growing out of divine revelation. 
theology n. The branch of theological science that treats of God. 
theoretical adj. Directed toward knowledge for its own sake without respect to applications. 
theorist n. One given to speculating. 
theorize v. To speculate. 
thereabout adv. Near that number, quantity, degree, place, or time, approximately. 
therefor adv. For that or this. 
thermal adj. Of or pertaining to heat. 
thermoelectric adj. Denoting electricity produced by heat. 
thermoelectricity n. Electricity generated by differences of temperature, 
thesis n. An essay or treatise on a particular subject. 
thoroughbred adj. Bred from the best or purest blood or stock. 
thoroughfare n. A public street or road. 
thrall n. One controlled by an appetite or a passion. 
tilth n. Cultivation. 
timbre n. The quality of a tone, as distinguished from intensity and pitch. 
timorous adj. Lacking courage. 
tincture n. A solution, usually alcoholic, of some principle used in medicine. 
tinge n. A faint trace of color. 
tipsy adj. Befuddled with drinks. 
tirade n. Harangue. 
tireless adj. Untiring. 
tiresome adj. Wearisome. 
Titanic adj. Of vast size or strength. 
toilsome adj. Laborious. 
tolerable adj. Moderately good. 
tolerance n. Forbearance in judging of the acts or opinions of others. 
tolerant adj. Indulgent. 
tolerate v. To passively permit or put up with. 
toleration n. A spirit of charitable leniency. 
topography n. The art of representing on a map the physical features of any locality or region with accuracy. 
torpor n. Apathy. 
torrid adj. Excessively hot. 
tortious adj. Wrongful. 
tortuous adj. Abounding in irregular bends or turns. 
torturous adj. Marked by extreme suffering. 
tractable adj. Easily led or controlled. 
trait n. A distinguishing feature or quality. 
trajectory n. The path described by a projectile moving under given forces. 
trammel n. An impediment. 
tranquil adj. Calm. 
tranquilize v. To soothe. 
tranquility n. Calmness. 
transalpine adj. Situated on the other side of the Alps. 
transact v. To do business. 
transatlantic adj. Situated beyond or on the other side of the Atlantic. 
transcend v. To surpass. 
transcendent adj. Surpassing. 
transcontinental adj. Extending or passing across a continent. 
transcribe v. To write over again (something already written) 
transcript n. A copy made directly from an original. 
transfer v. To convey, remove, or cause to pass from one person or place to another. 
transferable adj. Capable of being conveyed from one person or place to another. 
transferee n. The person to whom a transfer is made. 
transference n. The act of conveying from one person or place to another. 
transferrer n. One who or that which conveys from one person or place to another. 
transfigure v. To give an exalted meaning or glorified appearance to. 
transfuse v. To pour or cause to pass, as a fluid, from one vessel to another. 
transfusible adj. Capable of being poured from one vessel to another. 
transfusion n. The act of pouring from one vessel to another. 
transgress v. To break a law. 
transience n. Something that is of short duration. 
transient n. One who or that which is only of temporary existence. 
transition n. Passage from one place, condition, or action to another. 
transitory adj. Existing for a short time only. 
translate v. To give the sense or equivalent of in another language or dialect. 
translator n. An interpreter. 
translucence n. The property or state of allowing the passage of light. 
translucent adj. Allowing the passage of light. 
transmissible adj. That may e sent through or across. 
transmission n. The act of sending through or across. 
transmit v. To send trough or across. 
transmute v. To change in nature, substance, or form. 
transparent adj. Easy to see through or understand. 
transpire v. To come to pass. 
transplant v. To remove and plant in another place. 
transposition n. The act of reversing the order or changing the place of. 
transverse adj. Lying or being across or in a crosswise direction. 
travail n. Hard or agonizing labor. 
travesty n. A grotesque imitation. 
treacherous adj. Perfidious. 
treachery n. Violation of allegiance, confidence, or plighted faith. 
treasonable adj. Of the nature of betrayal, treachery, or breech of allegiance. 
treatise n. An elaborate literary composition presenting a subject in all its parts. 
treble adj. Multiplied by three. 
trebly adv. Triply. 
tremendous adj. Awe-inspiring. 
tremor n. An involuntary trembling or shivering. 
tremulous adj. Characterized by quivering or unsteadiness. 
trenchant adj. Cutting deeply and quickly. 
trepidation n. Nervous uncertainty of feeling. 
trestle n. An open braced framework for supporting the horizontal stringers of a railway-bridge. 
triad n. A group of three persons of things. 
tribune n. Any champion of the rights and liberties of the people: often used as the name for a newspaper. 
trickery n. Artifice. 
tricolor adj. Of three colors. 
tricycle n. A three-wheeled vehicle. 
trident n. The three-pronged fork that was the emblem of Neptune. 
triennial adj. Taking place every third year. 
trimness n. Neatness. 
trinity n. A threefold personality existing in the one divine being or substance. 
trio n. Three things grouped or associated together. 
triple adj. Threefold. 
triplicate adj. Composed of or pertaining to three related things or parts. 
triplicity n. The state of being triple or threefold. 
tripod n. A three-legged stand, usually hinged near the top, for supporting some instrument. 
trisect v. To divide into three parts, especially into three equal parts. 
trite adj. Made commonplace by frequent repetition. 
triumvir n. One of three men united coordinately in public office or authority. 
trivial adj. Of little importance or value. 
troublesome adj. Burdensome. 
truculence n. Ferocity. 
truculent adj. Having the character or the spirit of a savage. 
truism n. A statement so plainly true as hardly to require statement or proof. 
truthful adj. Veracious. 
turgid adj. Swollen. 
turpitude n. Depravity. 
tutelage n. The act of training or the state of being under instruction. 
tutelar adj. Protective. 
tutorship n. The office of a guardian. 
twinge n. A darting momentary local pain. 
typical adj. Characteristic. 
typify v. To serve as a characteristic example of. 
typographical adj. Pertaining to typography or printing. 
typography n. The arrangement of composed type, or the appearance of printed matter. 
tyrannical adj. Despotic. 
tyranny n. Absolute power arbitrarily or unjustly administrated. 
tyro n. One slightly skilled in or acquainted with any trade or profession. 
ubiquitous adj. Being present everywhere. 
ulterior adj. Not so pertinent as something else to the matter spoken of. 
ultimate adj. Beyond which there is nothing else. 
ultimatum n. A final statement or proposal, as concerning terms or conditions. 
ultramundane adj. Pertaining to supernatural things or to another life. 
ultramontane adj. Beyond the mountains, especially beyond the Alps (that is, on their Italian side). 
umbrage n. A sense of injury. 
unaccountable adj. Inexplicable. 
unaffected adj. Sincere. 
unanimous adj. Sharing the same views or sentiments. 
unanimity n. The state or quality of being of one mind. 
unavoidable adj. Inevitable. 
unbearable adj. Unendurable. 
unbecoming adj. Unsuited to the wearer, place, or surroundings. 
unbelief n. Doubt. 
unbiased adj. Impartial, as judgment. 
unbridled adj. Being without restraint. 
uncommon adj. Rare. 
unconscionable adj. Ridiculously or unjustly excessive. 
unconscious adj. Not cognizant of objects, actions, etc. 
unction n. The art of anointing as with oil. 
unctuous adj. Oily. 
undeceive v. To free from deception, as by apprising of the real state of affairs. 
undercharge v. To make an inadequate charge for. 
underexposed adj. Insufficiently exposed for proper or full development, as negatives in photography. 
undergarment n. A garment to be worn under the ordinary outer garments. 
underman v. To equip with less than the full complement of men. 
undersell v. To sell at a lower price than. 
undersized adj. Of less than the customary size. 
underhanded adj. Clandestinely carried on. 
underlie v. To be the ground or support of. 
underling n. A subordinate. 
undermine v. To subvert in an underhand way. 
underrate v. To undervalue. 
understate v. To fail to put strongly enough, as a case. 
undervalue v. To underestimate. 
underworld n. Hades. 
underwrite v. To issue or be party to the issue of a policy of insurance. 
undue adj. More than sufficient. 
undulate v. To move like a wave or in waves. 
undulous adj. Resembling waves. 
unfavorable adj. Adverse. 
ungainly adj. Clumsy. 
unguent n. Any ointment or lubricant for local application. 
unicellular adj. Consisting of a single cell. 
univalence n. Monovalency. 
unify v. To cause to be one. 
unique adj. Being the only one of its kind. 
unison n. A condition of perfect agreement and accord. 
unisonant adj. Being in a condition of perfect agreement and accord. 
Unitarian adj. Pertaining to a religious body that rejects the doctrine of the Trinity. 
unlawful adj. Illegal. 
unlimited adj. Unconstrained. 
unnatural adj. Artificial. 
unnecessary adj. Not essential under the circumstances. 
unsettle v. To put into confusion. 
unsophisticated adj. Showing inexperience. 
unspeakable adj. Abominable. 
untimely adj. Unseasonable. 
untoward adj. Causing annoyance or hindrance. 
unutterable adj. Inexpressible. 
unwieldy adj. Moved or managed with difficulty, as from great size or awkward shape. 
unwise adj. Foolish. 
unyoke v. To separate. 
up-keep n. Maintenance. 
upbraid v. To reproach as deserving blame. 
upcast n. A throwing upward. 
upheaval n. Overthrow or violent disturbance of established order or condition. 
upheave v. To raise or lift with effort. 
uppermost adj. First in order of precedence. 
uproarious adj. Noisy. 
uproot v. To eradicate. 
upturn v. To throw into confusion. 
urban adj. Of, or pertaining to, or like a city. 
urbanity n. Refined or elegant courtesy. 
urchin n. A roguish, mischievous boy. 
urgency n. The pressure of necessity. 
usage n. Treatment. 
usurious adj. Taking unlawful or exorbitant interest on money loaned. 
usurp v. To take possession of by force. 
usury n. The demanding for the use of money as a loan, a rate of interest beyond what is allowed by law. 
utilitarianism n. The ethical doctrine that actions are right because they are useful or of beneficial tendency.
utility n. Fitness for some desirable practical purpose. 
utmost n. The greatest possible extent. 
vacate v. To leave. 
vaccinate v. To inoculate with vaccine virus or virus of cowpox. 
vacillate v. To waver. 
vacuous adj. Empty. 
vacuum n. A space entirely devoid of matter. 
vagabond n. A wanderer. 
vagrant n. An idle wanderer. 
vainglory n. Excessive, pretentious, and demonstrative vanity. 
vale n. Level or low land between hills. 
valediction n. A bidding farewell. 
valedictorian n. Student who delivers an address at graduating exercises of an educational institution. 
valedictory n. A parting address. 
valid adj. Founded on truth. 
valorous adj. Courageous. 
vapid adj. Having lost sparkling quality and flavor. 
vaporizer n. An atomizer. 
variable adj. Having a tendency to change. 
variance n. Change. 
variant n. A thing that differs from another in form only, being the same in essence or substance. 
variation n. Modification. 
variegate v. To mark with different shades or colors. 
vassal n. A slave or bondman. 
vaudeville n. A variety show. 
vegetal adj. Of or pertaining to plants. 
vegetarian n. One who believes in the theory that man’s food should be exclusively vegetable. 
vegetate v. To live in a monotonous, passive way without exercise of the mental faculties. 
vegetation n. Plant-life in the aggregate. 
vegetative adj. Pertaining to the process of plant-life. 
vehement adj. Very eager or urgent. 
velocity n. Rapid motion. 
velvety adj. Marked by lightness and softness. 
venal adj. Mercenary, corrupt. 
vendible adj. Marketable. 
vendition n. The act of selling. 
vendor n. A seller. 
veneer n. Outside show or elegance. 
venerable adj. Meriting or commanding high esteem. 
venerate v. To cherish reverentially. 
venereal adj. Pertaining to or proceeding from sexual intercourse. 
venial adj. That may be pardoned or forgiven, a forgivable sin. 
venison n. The flesh of deer. 
venom n. The poisonous fluid that certain animals secrete. 
venous adj. Of, pertaining to, or contained or carried in a vein or veins. 
veracious adj. Habitually disposed to speak the truth. 
veracity n. Truthfulness. 
verbatim adv. Word for word. 
verbiage n. Use of many words without necessity. 
verbose adj. Wordy. 
verdant adj. Green with vegetation. 
verification n. The act of proving to be true, exact, or accurate. 
verify v. To prove to be true, exact, or accurate. 
verily adv. In truth. 
verity n. Truth. 
vermin n. A noxious or troublesome animal. 
vernacular n. The language of one’s country. 
vernal adj. Belonging to or suggestive of the spring. 
versatile adj. Having an aptitude for applying oneself to new and varied tasks or to various subjects. 
version n. A description or report of something as modified by one’s character or opinion. 
vertex n. Apex. 
vertical adj. Lying or directed perpendicularly to the horizon. 
vertigo n. Dizziness. 
vestige n. A visible trace, mark, or impression, of something absent, lost, or gone. 
vestment n. Clothing or covering. 
veto n. The constitutional right in a chief executive of refusing to approve an enactment. 
vicarious adj. Suffered or done in place of or for the sake of another. 
viceroy n. A ruler acting with royal authority in place of the sovereign in a colony or province. 
vicissitude n. A change, especially a complete change, of condition or circumstances, as of fortune. 
vie v. To contend. 
vigilance n. Alert and intent mental watchfulness in guarding against danger. 
vigilant adj. Being on the alert to discover and ward off danger or insure safety. 
vignette n. A picture having a background or that is shaded off gradually. 
vincible adj. Conquerable. 
vindicate v. To prove true, right, or real. 
vindicatory adj. Punitive. 
vindicative adj. Revengeful. 
vinery n. A greenhouse for grapes. 
viol n. A stringed instrument of the violin class. 
viola n. A musical instrument somewhat larger than a violin. 
violator n. One who transgresses. 
violation n. Infringement. 
violoncello n. A stringed instrument held between the player’s knees. 
virago n. A bold, impudent, turbulent woman. 
virile adj. Masculine. 
virtu n. Rare, curious, or beautiful quality. 
virtual adj. Being in essence or effect, but not in form or appearance. 
virtuoso n. A master in the technique of some particular fine art. 
virulence n. Extreme poisonousness. 
virulent adj. Exceedingly noxious or deleterious. 
visage n. The face, countenance, or look of a person. 
viscount n. In England, a title of nobility, ranking fourth in the order of British peerage. 
vista n. A view or prospect. 
visual adj. Perceptible by sight. 
visualize v. To give pictorial vividness to a mental representation. 
vitality n. The state or quality of being necessary to existence or continuance. 
vitalize v. To endow with life or energy. 
vitiate v. To contaminate. 
vituperable adj. Deserving of censure. 
vivacity n. Liveliness. 
vivify v. To endue with life. 
vivisection n. The dissection of a living animal. 
vocable n. a word, especially one regarded in relation merely to its qualities of sound. 
vocative adj. Of or pertaining to the act of calling. 
vociferance n. The quality of making a clamor. 
vociferate v. To utter with a loud and vehement voice. 
vociferous adj. Making a loud outcry. 
vogue n. The prevalent way or fashion. 
volant adj. Flying or able to fly. 
volatile adj. Changeable. 
volition n. An act or exercise of will. 
volitive adj. Exercising the will. 
voluble adj. Having great fluency in speaking. 
voluptuous adj. having fullness of beautiful form, as a woman, with or without sensuous or sensual quality. 
voracious adj. Eating with greediness or in very large quantities. 
vortex n. A mass of rotating or whirling fluid, especially when sucked spirally toward the center.
votary adj. Consecrated by a vow or promise. 
votive adj. Dedicated by a vow. 
vulgarity n. Lack of refinement in conduct or speech. 
vulnerable adj. Capable of receiving injuries. 
waif n. A homeless, neglected wanderer. 
waistcoat n. A vest. 
waive v. To relinquish, especially temporarily, as a right or claim. 
wampum n. Beads strung on threads, formerly used among the American Indians as currency. 
wane v. To diminish in size and brilliancy. 
wantonness n. Recklessness. 
warlike adj. Belligerent. 
wavelet n. A ripple. 
weak-kneed adj. Without resolute purpose or energy. 
weal n. Well-being. 
wean v. To transfer (the young) from dependence on mother’s milk to another form of nourishment. 
wearisome adj. Fatiguing. 
wee adj. Very small. 
well-bred adj. Of good ancestry. 
well-doer n. A performer of moral and social duties. 
well-to-do adj. In prosperous circumstances. 
whereabouts n. The place in or near which a person or thing is. 
whereupon adv. After which. 
wherever adv. In or at whatever place. 
wherewith n. The necessary means or resources. 
whet v. To make more keen or eager. 
whimsical adj. Capricious. 
whine v. To utter with complaining tone. 
wholly adv. Completely. 
wield v. To use, control, or manage, as a weapon, or instrument, especially with full command. 
wile n. An act or a means of cunning deception. 
winsome adj. Attractive. 
wintry adj. Lacking warmth of manner. 
wiry adj. Thin, but tough and sinewy. 
witchcraft n. Sorcery. 
witless adj. Foolish, indiscreet, or silly. 
witling n. A person who has little understanding. 
witticism n. A witty, brilliant, or original saying or sentiment. 
wittingly adv. With knowledge and by design. 
wizen v. To become or cause to become withered or dry. 
wizen-faced adj. Having a shriveled face. 
working-man n. One who earns his bread by manual labor. 
workmanlike adj. Like or befitting a skilled workman. 
workmanship n. The art or skill of a workman. 
wrangle v. To maintain by noisy argument or dispute. 
wreak v. To inflict, as a revenge or punishment. 
wrest v. To pull or force away by or as by violent twisting or wringing. 
wretchedness n. Extreme misery or unhappiness. 
writhe v. To twist the body, face, or limbs or as in pain or distress. 
writing n. The act or art of tracing or inscribing on a surface letters or ideographs. 
wry adj. Deviating from that which is proper or right. 
yearling n. A young animal past its first year and not yet two years old. 
zealot n. One who espouses a cause or pursues an object in an immoderately partisan manner. 
zeitgeist n. The intellectual and moral tendencies that characterize any age or epoch. 
zenith n. The culminating-point of prosperity, influence, or greatness. 
zephyr n. Any soft, gentle wind. 
zodiac n. An imaginary belt encircling the heavens within which are the larger 

Nationalism – A glance into the History of the World


Nationalism:

Nationalism has been one of the most influential of the various doctrinal constellations that have vied for man’s loyalties since the erosion of traditional religion. Despite protean local nations, it has re-appeared as a consistent set of demands and beliefs and social arrangements.

Again

Nationalism is a distinct ideological variety of social and political movement with a definite ‘directional tendency’, a recognizable profile and thrust.

In the whole history of people, its holiest moment is when it awakens from its unconsciousness, and for the first time thinks of its old holy rights. People who grasps its sense of nationality, with pleasure and love, can always celebrate its rebirth.

Nationalism represents a mass state of mind or national consciousness of comparatively recent origin, among the majority of peoples and is the result of a variety of convergent causes- race, instinct, language, religion, geography, administration and tradition – produced by the conditions of modern civilization. It is the outgrowth of the democratic idea that the State belonged to the masses of the nation as a whole, and thus it became akin to the independent development of each distinct group.

Nationalism stands for the historical process by which nationalities are transformed into political unity and for the legitimate right of people who form a distinct and vigorous nation or nationality to get a place in the comity of the nations in the world.

Hallwell opined that “nationalism is a form of collective egotism, rooted in the love of the familiar land and people”.

Other thinkers have also regarded nationalism as a historical and political concept, and the outcome of ethical aspirations and spiritual unity. Nationalism, being rooted in the gregarious instincts of men, has become a historical realty as well as process, but carried to its extremes, it has often degenerated into patriotic snobbery, jingoism and territorial aggrandizement.

Nationalism, originally meant that mankind is naturally divided into various nations and that these constitute the natural units of political sovereignty. But the modern connotation of the term means that, “it is a formulization of rationalization of national consciousness and as such it inevitably sough full expression in unified and independent statehood”.

Nationalism, in fact, is a spontaneous response to the force which in modern times have revolutionized the world. It is a product of the break with the old order of life and since the French Revolution it took a definite turn. The forces responsible for growth of nationalism, were essentially democratic, who mobilized the submerged elements and classes of society into new social dynamism, doing away with traditional relationship and making anew pattern of society.

Nationalism, being an occidental phenomenon by birth and nature, is characterized by a peculiar European idea, sponsored and propagated into a definite philosophy of politics and life, in the 18th and 19th century by the French Encyclopeadists, like Rousseau and Voltaire; German metaphysicians, like Fischte, Kant and Hegal; and the English Romantic poets like Shelley and Byron.

The Peculiar European term nationalism, means that a nation should coincide with one sate, but before the birth of this idea, there were people who were divided among several states, as the Germans and Italians were divided till the 18th century and there were states, which included several nations within their boundaries, such as the Ottoman Empire.

Nationalists writers have emphasized every kind of cultural and other criterion in stating out their claims for their ‘nation’, such as Mazzani pointed to Italy’s unique geography; Tilak to India’s worship of Kali; Blyden and Senghor to the blackness and spirituality of the Africans; in Greece, Israel, Burma, and Indonesia, religion has been most potent self-definer and provided a man subtle and solid foundation for national identity.

In short the core of nationalist doctrine is as under:

  1. The humanity is naturally divided into nations;
  2. That each nation has its own peculiar character
  3. That the source of all political power is the nation, the whole collectivity;
  4. That for freedom and self-realization, man must identify himself with a nation;
  5. That nations can be fulfilled only in their states;
  6. That loyalty to the nation-state overrides other loyalties;
  7. That the primary condition of global freedom and harmony is the strengthening of the nation-state.

Some of the themes which recur endlessly in the nationalist movements and their literature are: Identity, Purity, ‘the enemy’, historical roots, self-emancipation, building the new man and the new community, collective sovereignty and participation etc.

Fundamentally the doctrine of nationalism fuses three main ideals, to wit;

(a)   Collective self-determination

(b)  The expression of national character and individuality

(c)   The vertical division of the world into unique nations , each contributing its special genius to the common fund of humanity.

The growth of nationalism can be divided into three main periods: the first period begins in the 18th century, with the gradual dissolution of the medieval unity of Empire and Church and the establishment of National Church. In this period the nation was identified with the person of the sovereign. In this period, the advance of nationalism was really felt at the partition of Poland in 1772. It gave force to the Spanish resistance against the French Government from 1806 to 1813. It caused the defeat of Napoleon at Moscow and the revival of Germany after 1815.

The second period begins from the turmoil of the Napoleonic Wars or roughly with the Vienna Congress in 1815 and ended in 1914. In this period, the national forces were very successful and asserted their claim to the statehood, whether through a coalescence or through a breakup of the then existing units. Its founder was J.J. Rousseau, who after rejecting the embodiment of the nation with the person of the Sovereign or the ruling class, identified nation with the people. This principle was recognized first of all the American and French people in their respective revolutions against their ruling masters. It was the beginning of the democratization of nationalism, and was wholly alien to the nature and temper of the 18th century nationalism.

Although, the identification of the nation with the people was not very much encouraged by the statement at the Vienna Congress, yet the democratization of nationalism continued steadily and became a definite political ideal in 1848. It was time when nationalism represented a change from sentiment to program. As Lord Morely pointed out as under:

“Nationalism, in this period, from instinct became an idea; from idea, abstract principle; the fervid pre-possession ending where it is today, in dogma, whether accepted or evaded.”

But the dogma was both revotionallary and creative in this period. The third period roughly began since 1870, but took a definite start from 1914. During this period a new social order replaced the older one, more or less, among all the nations of the world; political power became synonymous with the economic power and many new nations appeared on the political horizon of the world. Particularly the modern Arab nations are the product of the Treaty of Versailles concluded in 1919.

In this period nationalism also found al close affinity with socialism, and the right of self-determination became standing invitation to the nations to secede from the Empires or from the alien rule. The bare fact that, at present, there are almost more than 140 nations or independent political units, goes far by itself to explain the spread of nationalism in this period. In Europe, nationalism was the outcome of the break-up of feudal set-up of the society and State, while in Afro-Asian counties; it is the offshoot of colonial era. Disintegration of the older forms of society, communal life and the emergence of a common man as a new force is the socio-political order.

The philosophy of nationalism is not without its critics. Edmund Burke, Thomas Carlyle, Lord Hugh Cecil and various other thinkers said that uncontrolled mass nationalism is crude dangerous and disintegrating force; because masses are generally inert and tools in the hands of their leaders, as we have in the case of Axis powers during the Second World War E. Kedourie, one of the most ardent critics of the idea of nationalism has remarked about tit as follows:

Nationalism is a doctrine invented in Europe at the beginning of 19th century. It pretends to supply a criterion for the determination of the unit of population proper to enjoy a government exclusively its own, for the legitimate exercise of power in the state and for the right organization of society of states.”

Briefly the doctrine holds that humanity is naturally divided into nations, that nations are known by certain characteristics which can be ascertained and that only legitimate type of government is national self-government.

Further, Kedourie regards nationalism as one of the most pernicious doctrines that has been inflicted on the suffering humanity. It is an antiquarian irrelevance, a baneful invention of some misguided German philosophers, supported by the frustrations of obscure middle-class writes, low-born sons of artisans, farmers and pastors.

It has introduced an extremist style into politics. It has confused with interests. Instead of peace and prosperity, it has brought new conflicts, exacerbated tensions and catastrophes to numberless million of the innocent people.

 

 

 

List of Important Books


Glimpses of World History
Glimpses of World History (Photo credit: Wikipedia)
Sr. No Book Author

1

A farewell to Arms Ernest Hemingway

2

Pride and Prejudice Jane Austen

3

India Wins Freedom Mulana Abul Kalam Azad

4

Nineteen Eighty-Four George Orwell

5

Gandhi and Stalin Louis Fisher

6

Sword fo Tipu Sultan B.S Gidvani

7

War and Peace Leo Tolstoy

8

Spirit of Laws Motesquieu

9

The City of the Saints Sir Richard F. Burton

10

My experiments with truths M. K Gandhi

11

Crossing the Threshold of Hope Pop John Paul – II

12

Remembering Babylon David Malouf

13

Daughter of the East Benazir Bhutto

14

Bluest Eye Tony Morrison

15

Glimpses of World History Jawaharlal Nehru

16

Shahnama Firdausi

17

All Under Heaven Pearl S. Buck

18

Gulliver’s Travels Jonathan Swift

19

To live or not to live Nirad C. Chaudhry

20

Tahqiq-i-Hind Alberuni

21

Around the world in Eighty Days Jules Verne

22

The Prince Nicollo Michavelli

23

Das Kapital Karl Marx

24

Mankind and Mother Earth Arnold Josiph Tonybee

25

A prisoner’s Scrap-book L.K Advani

26

Zulfi, My Friend Peelo Modi

27

The Power and Glory Graham Greene

28

Life Divine Sri Auobindo

29

Edwina Mountabatton- A life of her own Edwina Mountabatton

Highest Military Awards


Nishan-e-Haider is the highest military award ...
Nishan-e-Haider is the highest military award given by Pakistan. (Photo credit: Wikipedia)
Sr. No Military Award Country

1

Victoria Cross Britain

2

Legion of Honor France

3

Iron Cross Germany

4

Param Vir Chakra India

5

Order of the Rising Sun Japan

6

Nishan-i-Haider Pakistan

7

Medal of Honor USA

8

Medal for Valour Italy

9

Order of the Patriotic War Russia

10

Belgium Military Cross

11

Bir Sreshtho Bangladesh

12

Israel Medal of Valor

Geographical Epithets – Cities of The World and their alternative names


Which city is called the Granite City

Aberdeen (Scotland)

Which city is called the city of Eagles

Sialkot

Which city is called the city of Golden Temple

Amritsar

Which city is called the city of Water

Venice

Which city is called the city of Angels

Los Angeles

Which city is called the city Gateway to the East

Beirut

Which city is called the little Pakistan

Bradford

Which city is called the Pyramid City

Cairo

Which city is called the city of Bazaars

Cairo

Which city is called the city of Space Flights

Cape Kennedy

Which city is called the Manchester of Pakistan

Faisalabad

Which city is called the city of conferences

Geneva

Which city is called the city of Rams

Guangzhou

Which city is called the Gateway of Pakistan

Karachi

Which city is called the city of Cannals

Venice

Which city is called city of Palaces

Mexico City

Which city is called forbidden City

Lhasa

Which city is called Gateway of India

Mumbai

Which city is called City of Cosmonauts

Moscow

Which city is called City of Skyscrapers

New York

Which city is called the city of eternal Spring

Quito

Which city is called the city of Popes

Vatican City

Which city is called land of Seven Hills

Rome

Which city is called The Golden Gate City

San Francisco

Which city is called the city of Roses and Nightingales

Shiraz

Which city is called Queen of the Baltic

Stockholm

Which city is called city of Gondolas

Venice

Geographical Epithets


Which Country is called the Buffer State of Asia

Afghanistan

Which country is called ‘Land of fertile fields’

Algeria

Which country is called Land of golden fleece

Australia

Which country is called Remnant of a might empire

Austria

Which country is called Isle of June

Bahamas

Which country is called Isle of Pearl

Bahrain

Which country is called Land of Golden Fibre

Bangladesh

Which country is called Cockipt of Europe

Belgium

Which country is called cross road of Europe

Belgium

Which country is called land of lilies

Canada

Which country is called land of contrast

Colombia

Which country is called pearl of Antilles

Cuba

Which country is called Homeland of the Viking Empire

Denmark

Which country is called Gift of the Nile

Egypt

Which country is called Land of Queen of Sheba

Yemen

Which country is called Land of Thousand lakes

Finland

Which country is called key to Mediterranean  

Gibraltar

Which country is called Pillar of Hercules

Gibraltar

Which country is called Whiteman’s grave

Guinea

Which country is called Island of Hispaniola

Haiti

Which is called The Sorrow of China

Hwang Hoo

Which country is called Land of thousand islands

Indonesia

Which country is called the site of ancient civilization

Iraq

Which country is called Emerald Island

Ireland

Which country is called Great Britain of the Pacific

Japan

Which country is called land of mystics and prayers

India

Which country is called Land of Rising Sun

Japan

Which country is called land of Morning Calm

South Korea

Which country is called land of Milk and Honey

Lebanon

Which country is called land of Amber

Lithuania

Which country is called George Cross Island

Malta

Which country is called land of rice and teak

Myanmar

Which country is called land of Mountains

Nepal

Which country is called Land of Druk-yul

Bhutan

Which country is called the Flower garden of Europe

Netherlands

Which country is called Britain of the South

New Zealand

Which country is called Land of Cakes

Scotland

Which country is called Land of Midnight Sun

Norway

Which country is called Land of Pure People

Pakistan

Which country is called Horn of Africa

Somalia

Which country is called Switzerland of Africa

Swaziland

Which country is called Playground of Europe

Switzerland

Which country is called the land of White Elephants

Thailand

Which country is called Land of free People

Thailand

Which country is called the land of Smiles

Thailand

Which country is called the land of Opportunities

USA

One Thing Obamacare Can’t Fix: Bad Addiction Treatment


Ideas

Correction appended, March 26, 2014.

After weeks spent offering up increasingly desperate excuses for the glitchy rollout of Obamacare’s insurance exchanges, Health and Human Services Secretary Kathleen Sebelius seemed elated to change the subject, at least for a moment, when last week she announced regulations that will mean that almost all Americans with health insurance will be fully covered for the treatment of mental illness, including addiction, at least as well as they’re covered for physical diseases. The regulations were trumpeted as part of the President’s plans for curbing gun violence, but they have enormous implications for untreated addiction, which alone costs the nation $420 billion a year, mostly in health care, criminal justice and lost productivity.

(MORE:Viewpoint: We Need to Rethink Rehab)

The new rules are comprehensive, but it’s impossible to know how they’ll be interpreted, monitored and policed. Treating mental illness isn’t easy or cheap…

View original post 640 more words

List of Vitamins and Food that have it!


Following is the list of Vitamins necessary for a healthy body. Please go through and self assess your body and try to over come the deficiency that you think you have. If symptoms persist then you better consult any general physician for detailed diagnosis.

Vitamin Helps To Food to Get it
VITAMIN A(Retinol, retinal, and retinoic acid — three active forms of vitamin A in the body — are retinoid, “preformed” vitamin A. Beta carotene can easily be converted to vitamin A as needed.) Necessary for vision Lycopene may lower prostate cancer risk. Keeps tissues and skin healthy.

Plays an important role in bone growth.

Diets rich in the carotenoids alpha carotene and lycopene seem to lower lung cancer risk.

Carotenoids act as antioxidants.

Foods rich in the carotenoids lutein and zeaxanthin may protect against cataracts.

Sources of retinoids:

Beef, liver, eggs, shrimp, fish, fortified milk, cheddar cheese, Swiss cheese
Sources of beta carotene:

sweet potatoes, carrots, pumpkins, squash, spinach, mangoes, turnip greens

THIAMIN  Helps convert food into energy needed for well skin, hair, muscles, and brain Pork chops, ham, soymilk, watermelons, acorn squash
RIBOFLAVIN Helps convert food into energy needed for healthy skin, hair, blood, and brain Milk, yogurt, cheese, whole and enriched grains and cereals, liver
NIACIN  Helps convert food into energy. Essential for healthy skin, blood cells, brain, and nervous system Meat, poultry, fish, fortified and whole grains, mushrooms, potatoes, peanut butter
PANTOTHENIC ACID  Helps convert food into energy. Helps make lipids (fats), neurotransmitters, steroid hormones, and hemoglobin Wide variety of nutritious foods, including chicken, whole grains, broccoli, mushrooms, avocados, tomato products
VITAMIN B6 Aids in lowering homocysteine levels and may reduce the risk of heart disease. Helps convert tryptophan to niacin and serotonin, a neurotransmitter that plays key roles in sleep, appetite, and moods. Helps make red blood cells Influences cognitive abilities and immune function Meat, fish, poultry, legumes, tofu and other soy products, potatoes, noncitrus fruits such as bananas and watermelons
Vitamin B12 Aids in lowering homocysteine levels and may lower the risk of heart disease Assists in making new cells and breaking down some fatty acids and amino acidsProtects nerve cells and encourages their normal growth Helps make red blood cells Meat, poultry, fish, milk, cheese, eggs, fortified cereals, fortified soymilk
BIOTIN Helps convert food into energy and synthesize glucose helps make and break down some fatty acids needed for healthy bones and hair Many foods, including whole grains, organ meats, egg yolks, soybeans, and fish
VITAMIN C(ascorbic acid) Foods rich in vitamin C may lower the risk for some cancers, including those of the mouth, esophagus, stomach, and breast.  Long-term use of supplemental vitamin C may protect against cataracts . Helps make collagen, a connective tissue that knits together wounds and supports blood vessel walls . Helps make the neurotransmitters serotonin and norepinephrine Acts as an antioxidant, neutralizing unstable molecules that can damage cellsBolsters the immune system Fruits and fruit juices (especially citrus), potatoes, broccoli, bell peppers, spinach, strawberries, tomatoes, Brussels sprouts
CHOLINE Helps make and release the neurotransmitter acetylcholine, which aids in many nerve and brain activities. Plays a role in metabolizing and transporting fats Many foods, especially milk, eggs, liver, and peanuts
VITAMIN D(calciferol) Helps maintain normal blood levels of calcium and phosphorus, which strengthen bones. Helps form teeth and bones Supplements can reduce the number of non-spinal fractures Fortified milk or margarine, fortified cereals, fatty fish
VITAMIN E(alpha-tocopherol) Acts as an antioxidant, neutralizing unstable molecules that can damage cells Protects vitamin A and certain lipids from damage Diets rich in vitamin E may help prevent Alzheimer’s disease. Supplements may protect against prostate cancer Wide variety of foods, including vegetable oils, salad dressings and margarines made with vegetable oils, wheat germ, leafy green vegetables, whole grains, nuts
FOLIC ACID(foliate, flacon) Vital for new cell creation. Helps prevent brain and spine birth defects when taken early in pregnancy; should be taken regularly by all women of child-bearing age since women may not know they are pregnant in the first weeks of pregnancy Can lower levels of homocysteine and may reduce heart disease risk May reduce risk for colon cancer Offsets breast cancer risk among women who consume alcohol Fortified grains and cereals, asparagus, okra, spinach, turnip greens, broccoli, legumes like black-eyed peas and chickpeas, orange juice, tomato juice
VITAMIN K(phylloquinone, menadione) Activates proteins and calcium essential to blood clotting May help prevent hip fractures Cabbage, liver, eggs, milk, spinach, broccoli, sprouts, kale, collards, and other green vegetables
Mineral (common names) Benefits Good food sources
CALCIUM Builds and protects bones and teeth Helps with muscle contractions and relaxation, blood clotting, and nerve impulse transmission Plays a role in hormone secretion and enzyme activation Helps maintain healthy blood pressure Yogurt, cheese, milk, tofu, sardines, salmon, fortified juices, leafy green vegetables, such as broccoli and kale (but not spinach or Swiss chard, which have binders that lessen absorption)
CHLORIDE Balances fluids in the body A component of stomach acid, essential to digestion Salt (sodium chloride), soy sauce, processed foods
CHROMIUM Enhances the activity of insulin, helps maintain normal blood glucose levels, and is needed to free energy from glucose Meat, poultry, fish, some cereals, nuts, cheese
COPPER Plays an important role in iron metabolism Helps make red blood cells Liver, shellfish, nuts, seeds, whole-grain products, beans, prunes
FLUORIDE Encourages strong bone formation Keeps dental cavities from starting or worsening Water that is fluoridated, toothpaste with fluoride, marine fish, teas
IODINE Part of thyroid hormone, which helps set body temperature and influences nerve and muscle function, reproduction, and growth Prevents goiter and a congenital thyroid disorder Iodized salt, processed foods, seafood
IRON Helps hemoglobin in red blood cells and myoglobin in muscle cells ferry oxygen throughout the body Needed for chemical reactions in the body and for making amino acids, collagen, neurotransmitters, and hormones Red meat, poultry, eggs, fruits, green vegetables, fortified bread and grain products
MAGNESIUM Needed for many chemical reactions in the body Works with calcium in muscle contraction, blood clotting, and regulation of blood pressure Helps build bones and teeth Green vegetables such as spinach and broccoli, legumes, cashews, sunflower seeds and other seeds, halibut, whole-wheat bread, milk
MANGANESE Helps form bones Helps metabolize amino acids, cholesterol, and carbohydrates Nuts, legumes, whole grains, tea
MOLYBDENUM Part of several enzymes, one of which helps ward off a form of severe neurological damage in infants that can lead to early death Legumes, nuts, grain products, milk
PHOSPHORUS Helps build and protect bones and teeth Part of DNA and RNAHelps convert food into energy Part of phospholipids, which carry lipids in blood and help shuttle nutrients into and out of cells Wide variety of foods, including milk and dairy products, meat, fish, poultry, eggs, liver, green peas, broccoli, potatoes, almonds
POTASSIUM Balances fluids in the body Helps maintain steady heartbeat and send nerve impulses Needed for muscle contractions A diet rich in potassium seems to lower blood pressure Getting enough potassium from your diet may benefit bones Meat, milk, fruits, vegetables, grains, legumes
< b>SELENIUM Acts as an antioxidant, neutralizing unstable molecules that can damage cells Helps regulate thyroid hormone activity Organ meats, seafood, walnuts, sometimes plants (depends on soil content), grain products
SODIUM Balances fluids in the body Helps send nerve impulses Needed for muscle contractions Impacts blood pressure; even modest reductions in salt consumption can lower blood pressure Salt, soy sauce, processed foods, vegetables
SULFUR Helps form bridges that shape and stabilize some protein structures Needed for healthy hair, skin, and nails Protein-rich foods, such as meats, fish, poultry, nuts, legumes
ZINC Helps form many enzymes and proteins and create new cells Frees vitamin A from storage in the liver Needed for immune system, taste, smell, and wound healing When taken with certain antioxidants, zinc may delay the progression of age-related macular degeneration Red meat, poultry, oysters and some other seafood, fortified cereals, beans, nuts