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radical, in chemistry

(Encyclopedia)radical, in chemistry, group of atoms that are joined together in some particular spatial structure and that take part in most chemical reactions as a single unit. Important inorganic radicals include...

radical, in mathematics

(Encyclopedia)radical, in mathematics, symbol () placed over a number or expression, called the radicand, to indicate a root of the radicand. When used without a sign or index number, as in 4, it designates the pos...

rape, in botany

(Encyclopedia)rape, in botany, annual herb (Brassica napus) of the family Cruciferae (or Brassicaceae; mustard family), belonging to the same genus as the cabbage, the mustard plant, and the turnip (which it resemb...

rape, in law

(Encyclopedia)rape, in law, the crime of sexual relations, often specifically sexual intercourse, without the consent of the victim, often through force or threat of violence. The victim is deemed legally incapable...

ray, in zoology

(Encyclopedia)ray, extremely flat-bodied cartilaginous marine fish, related to the shark. The pectoral fins of most rays are developed into broad, flat, winglike appendages, attached all along the sides of the head...

ray, in physics

(Encyclopedia)ray, in physics, term denoting the straight line along which light or other form of radiation is propagated from its source. It generally refers to the line of propagation of waves but is also applied...

seal, in zoology

(Encyclopedia)seal, carnivorous aquatic mammal with front and hind feet modified as flippers, or fin-feet. The name seal is sometimes applied broadly to any of the fin-footed mammals, or pinnipeds, including the wa...

saint, in Christianity

(Encyclopedia)saint [O.Fr., from Latin sanctus=holy], in Christianity, a person who is recognized as worthy of veneration. Accounts of saints' lives have been favorite reading material for many, and at times thei...

saki, in zoology

(Encyclopedia)saki: see monkey.

sale, in law

(Encyclopedia)sale, in law, transfer of ownership in return for money. An exchange of goods for goods is termed barter, but the distinction between sale and barter is mainly technical; laws that govern one govern t...