- noun the offence of a person’s having sexual intercourse with a close relative such their daughter, son, mother or father
- noun a notifiable offence of having sexual intercourse with a close relative such as a daughter, son, mother or father
- noun an act of sexual intercourse or other sexual activity with so close a relative, that it is illegal or culturally not allowed
Origin & History of “incest”
Etymologically, incest is virtually the same word as unchaste. It was borrowed from Latin incestus, a noun use of an adjective formed from the negative prefix in- and castus ‘pure’ (source of English chaste). The Latin word denoted ‘unchastity’ in general, but in practice was often applied specifically to ‘sexual contact between close relatives’.