Competitive Exams: Terminology

  • Avalanche: They are large accumulations of snow which split off in summer with great noise and go down. Tearing and smashing at the bottom, causing loss of life to travellers sometimes.
  • Amber: Fossilised resin of old conifers, generally occuring on the shores of the seas. These are treated gem stones and believed to have magical powers.
  • Asteroids: They are small bodies which revolve round the sun between the orbits of Mars and Jupiter.
  • Aphelion: In contrast to Perihelion, aphelion is the point on earth's orbit when it is farthest from the sun. In perihelion it is nearest to the sun.
  • Atoll: It is the name given to a coral is a kind or reef, an incomplete ring including a lagoon. Many islands in the Pacific are called ‘atolls.’
  • Continental Shelf: The term is used by geographers to denote a kind of pedestal moon which the continents seem to rest in the ocean. It is a kind of marine plain along the coat which stretches from zero to 200 metres in depth. It slopes steadily towards the sea. After a depth of about 200 metres is formed the continental slope which named the ocean rim and which separates the continental shelf.
  • Conical Projection: A part of the earth projected upon a tangent cone.
  • Climate: It is the average weather condition of a place or region. The climate of a place is determined by its distance from the equator, height above the sea level, distance from the sea, velocity and extent of winds and direction of mountains. It also depends on the nature of the soil, slope of land, availability of forests and the direction of ocean currents.
  • Cyclones and Anticyclones: Sometimes there happens to be low pressure in the middle of atmosphere and high pressure all round it. Winds blow from outside inwards in anticlockwise direction in the form of whirling storms. This is a cyclone. On the other hand, if there is high pressure in the centre and low pressure. All round, winds blow outwards in clockwise direction and the sky clears up. This is an anticylone. The direction mentioned here holds good for the Northern hemisphere. In the Southern hemisphere the cyclonic winds blow clockwise and the anticyclonic winds blow anticlockwise.
  • Canyon: It is the name given to a valley which has a steep bank.
  • Delta: An alluvial deposit on the mouth of a river.
  • Doldrums: The parts of an ocean lying between 5° North and 5° South of Equator. Calm and baffling winds alternate here making navigation difficult.
  • Dew: It is water formed by condensation of water vapour as air cools.
  • Deciduous Forests: These are forests which shed their leaves at certain seasons as distinguished from evergreen or permanent foliage trees or shrubs.
  • Erosion: Gradual destruction of land due to action of natural agents.
  • Equinox: It stands for two dates in a year approximately March 21 and September 23 when J day and night are equal. Equinox of March 21 is called Spring Equinox while that of September 22 is called ‘Autumnal Equinox’
  • Equator: Equator represents the imaginary I line passing round the earth midway between the north and south poles. It thus divides the earth into two equal halves (the Northern and Southern Hemispheres).
  • Fauna and Flora: This term indicates the characteristics of animals and plants of a particular region.
  • Fossils: The remains of animals or plants deposited in the rocks of earth's crust.
  • Gulf Stream: It is a kind ocean current from the Gulf of Mexico proceeding along the east coast of the United States and later on following the Westerlies of Europe. Then it divides into two parts, one warm current touching the coast of northwest Europe and the other cold current touching the coast of northwest Africa.
  • Glaciers: Masses of ice caused by SHOW on a mountain slowly coming down till they melt or break up. Iceberg: Huge floating mass of ice fonned in the sea or lake due to fall of temperature to freezing point. Isotherms: These are lines joining the places having the same average temperature.
  • Igneous rock: This is molten material that is solidified on cooling like basalt, granite, etc.
  • Isobars: These are lines connecting places having the same barometric pressure.
  • Leap Year: This year which has 29 days of February occurs once in four years owing to the fact that the earth takes 365 days, 5 hours, 45 minutes arid 46 seconds to complete one revolution round the sun, but as the world has fixed 365 days for a year, it gets added in the calendar every fourth year. This is called the Leap Year.
  • Littoral Forests: These are situated near the seashore on lands near the coast or beach or in the places between high and low tide marks
  • Latitude: It is the distance of a place between the north and south of equator. Longitude of a Place is the distance, east or west, of a fixed meridian.
  • Lunar Eclipse: It is the partial or complete obscuration of the moon's surface with the earth coming in between the sun and the moon. The moon loses its bright illumination by the sun and its disc becomes only faintly visible.
  • Lagoon: It is a geographical term indicating the stretch of shallow water opening out into the sea. The best example of lagoon is Venice in Europe which is a city built on lagoons. Motions of the Earth: The earth has two motions-round its axis or the daily motion at to the plane of the orbit and revolution around the sun on its orbit.
  • Milky Way: It a combination of stars visible on clear nights at particular angles to each other. Meridian of Longitude: These are lines drawn on a map or globe showing the longitude of a place. These lines join the north and south poles cutting the Equator at right angles.
  • Map Projection: It is the method by which the curved surface of the earth is depicted on a flat surface or a plane.
  • Oasis: It is a localized area surrounded by desert but moist enough to support vegetation. Water in an oasis sometimes comes from the ground and sometimes from water wells or springs in depression.
  • Parallels of Latitude: These are lines drawn on a map or globe showing the latitude of a place.
  • Prairies: Are the temperate grasslands of South America. Prairies are the temperate grasslands of North America.
  • Rock: It is a mineral matter forming the solid crust of the earth. It can be sedimentary, igneous or metamorphic.
  • Rainbow: It is an arc of color shading through the spectrum from red to violet; it is formed by refraction and reflection of sunlight by rain drops. The radius of the primary bow takes an angle of about 41 per cent from the eye with red on the outside:
  • Solar Eclipse: It is the partial or complete obscuration of the sun by moon coming in between the sun and the earth. Stratus: A formless cloud characteristic of a drizzle but not heavy rain.
  • Sideral Day: Twilight from the sky when the sun is below the horizon, i.e.. either in the morning or in the evening.
  • Snowline: It is the line on a mountain slope representing the lower limit of perpetual snow. It usually prevails at an altitude of 18, 000 feet.
  • Sedimentary Rock: This rock is cemented material accumulated with time. Orbit: It is the elliptical path or earth's revolution round the sun.
  • Savanna: It is the name given to the region bordering the equatorial forest in northern and southern hemispheres. Savannas usually prevail in Africa
  • Thermosphere: It is the middle layer of ionosphere with a temperature of 212° F.
  • Tornado: A violent whirlwind characterized by a black-tunnel-shaped cloud hanging by heavy cumulus.
  • Terai: Terai refers to the strip of marshy land stretching parallel to the lower ranges of Himalayas in northern India. It is a moist land.