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cell, in biology

(Encyclopedia)CE5 Animal cell cell, in biology, the unit of structure and function of which all plants and animals are composed. The cell is the smallest unit in the living organism that is capable of integrati...

porcupine, in zoology

(Encyclopedia)porcupine, member of either of two rodent families, characterized by having some of its hairs modified as bristles, spines, or quills. The quills are loosely attached to the porcupines' skin and pull ...

aids, in feudalism

(Encyclopedia)aids, in feudalism, type of feudal due paid by a vassal to his suzerain (overlord). Aids varied with time and place, although in English-speaking countries aids were traditionally due on the knighting...

chord, in music

(Encyclopedia)chord, in music, two or more simultaneously sounding pitches. In tonal music the fundamental chord is called the triad. It consists of three pitches, two a perfect fifth apart and a third pitch a majo...

crane, in zoology

(Encyclopedia)crane, large wading bird found in marshes in the Northern Hemisphere and in Africa. Although sometimes confused with herons, cranes are more closely related to rails and limpkins. Cranes are known for...

gall, in botany

(Encyclopedia)gall, abnormal growth, or hypertrophy, of plant tissue produced by chemical or mechanical (e.g., the rubbing together of two branches) irritants or hormones. Chemical irritants are released by parasit...

hail, in meteorology

(Encyclopedia)hail, precipitation in the form of pellets composed of ice or of ice and snow, occurring at any time of the year, usually during the passage of a cold front or during a thunderstorm. Small hailstones ...

mine, in warfare

(Encyclopedia)mine, in warfare, term formerly applied to a system of tunnels dug under an army fortification and ending in a chamber where either explosives were placed to be detonated at a chosen moment or the sup...

impressionism, in painting

(Encyclopedia)impressionism, in painting, late-19th-century French school that was generally characterized by the attempt to depict transitory visual impressions, often painted directly from nature, and by the use ...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...