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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...

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...

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...

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...