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scale, in zoology

(Encyclopedia)scale, in zoology, an outgrowth, either bony or horny, of the skin of an animal. The major component of the scales of fishes is bone, and they are formed directly in the skin membrane as the fish grow...

Uranus , in astronomy

(Encyclopedia)Uranus yo͝orāˈnəs, yo͝orˈə– [key], in astronomy, 7th planet from the sun, at a mean distance of 1.78 billion mi (2.87 billion km), with an orbit lying between those of Saturn and Neptune; its...

fatigue, in physiology

(Encyclopedia)fatigue, in physiology, inability to perform reasonable and necessary physical or mental activity. Muscle fatigue, for example, results when the contractile properties of muscle are reduced, and conti...

sin, in religion

(Encyclopedia)sin, in religion, unethical act. The term implies disobedience to a personal God, as in Judaism, Christianity, and Islam, and is not used so often in systems such as Buddhism where there is no persona...

plum, in botany

(Encyclopedia)plum, common name for a tree of any of many species of the genus Prunus of the family Rosaceae (rose family) and for its fruit, a drupe. The plum is generally cultivated in the temperate zones, though...

dispersion, in chemistry

(Encyclopedia)dispersion, in chemistry, mixture in which fine particles of one substance are scattered throughout another substance. A dispersion is classed as a suspension, colloid, or solution. Generally, the par...

drainage, in agriculture

(Encyclopedia)drainage, in agriculture, the removal of excess water from the soil, either by a system of surface ditches, or by underground conduits if required by soil conditions and land contour. Diesel or centri...

modulation, in communications

(Encyclopedia)CE5 Modulation modulation, in communications, process in which some characteristic of a wave (the carrier wave) is made to vary in accordance with an information-bearing signal wave (the modulatin...

code, in law

(Encyclopedia)code, in law, in its widest sense any body of legal rules expressed in fixed and authoritative written form. A statute thus may be termed a code. Codes contrast with customary law (including common la...

horn, in zoology

(Encyclopedia)horn, in zoology, one of a pair of structures projecting from the head of a hoofed animal, used chiefly as a weapon. In cattle, sheep, Old World antelopes, and related animals the horns are permanent ...