Terminology
The English word incest is derived from the Latin incestus, which has a general meaning of "impure, unchaste". It was introduced into Middle English, both in the generic Latin sense, and in the narrow modern sense. The generic Latin sense preserved throughout the Middle English period. The derived adjective incestuous appears in the 16th century. Prior to the introduction of the Latin term, incest was known in Old English as sibbleger (from sibb 'kinship' + leger 'to lie') or mǣġhǣmed (from mǣġ 'kin, parent' + hǣmed 'sexual intercourse') but in time, both words fell out of use.
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