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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...

Müller, Johannes Peter

(Encyclopedia)Müller, Johannes Peter mŭlˈər [key], 1801–58, German physiologist and anatomist. From 1833 until the end of his career he was professor at Berlin. He was famed as a teacher; for his extensive r...

Sète

(Encyclopedia)Sète, formerly Cette both: sĕt [key], town (1990 pop. 41,916), Hérault dept., S France, in Languedoc, on the Mediterranean. It is one of the most important commercial and fishing ports of S France,...

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...

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...

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...

Hydra, in astronomy

(Encyclopedia)Hydra, in astronomy, southern constellation lying S of Corvus, Crater, Virgo, Leo, and Cancer. It is a long, slender, winding constellation traditionally depicted as a snake and known also as the Wate...

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...