Incestuous
/ɪnˈsɛs.tʃu.əs/noun
Involving or characterized by sexual relations between closely related people.
Did you know?The core Latin word incestus originally meant “impure” or “unchaste,” and only later became the specific legal/moral term for sex within the family—proof that words can narrow from ritual pollution to taboo crime.
Etymological Timeline
Latin prehistory
PIE
*en-
“in, within”
Latin
Latin
incestus
“unchaste, impure, morally defiled”
Late Latin
Latin
incestuosus
“full of impurity; incestuous”
Old French
Old French
incestueux
“incestuous, violating sexual taboo”
Middle English
English
incestuous
“pertaining to incest; sexually taboo within a family”
Modern English
English
incestuous
“involving or characterized by incest”
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