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Pronunciation: in'sest


  1. Sexual relations between people closely related by blood, especially between parent and child, brother and sister.
  2. The crime of sexual relations between persons related by blood, where such cohabitation is prohibited by law.

[L. incestus, unchaste, fr. in-, not, + castus, chaste]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.