Entry 2 senses Webster, 1913 Bestiality /bĕs-chăl'-ĭt-ē/ · Bes·tial·i·ty · IPA /ˈbistiˌælɪti/ 01 n. The state or quality of being bestial. 1. The state or quality of being bestial. 2. Unnatural connection with a beast.