n. 1. Sexual relations between persons who are so closely related that their marriage is illegal or forbidden by custom. 2. The crime of sexual relations with a person defined by statute as too closely related. [Middle English, from Latin incestum, from neuter of incestus, impure, unchaste : in-, not; see IN-1 + castus, pure, chaste; see kes- in the Appendix of Indo-European roots.] |
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