custom, habitual group pattern of behavior that is transmitted from one generation to another and is not biologically determined. Since societies are perpetually changing, no matter how slowly, all customs are basically impermanent. If short-lived, they are more properly called fashions. Customs form the core of human culture and are stronger and more persistent in preindustrial societies than in industrial ones, in rural than in urban areas. When formalized in the social or religious sphere it leads to ethics, and when enforced in the sphere of rights and duties, custom leads to law. See folkways; mores.

In law, long-established practice common to many or to a particular place or institution and generally recognized as having the force of law. In England during the Anglo-Saxon period, local customs formed most laws affecting family rights, ownership and inheritance, contracts, and violence between individuals. The Norman conquerors granted the validity of customary law, adapting it to their feudal system. In the 13th and 14th centuries, English law was given statutory authority under the crown, making the “customs of the realm” England's common law. Seealso culture; folklore; myth; taboo.

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