Definition from Wiktionary, the free dictionary
bestiality (plural bestialities)
- (archaic) A status of lower animal.
- (archaic) An animal-like instinct or behaviour.
- (archaic) A mark, trait, or emblem of a beast.
- "What's your bestiality?" (What's your mark?)
- Sexual activity between a human and another species.
- (dated) Bestial in nature, savagery, inhumanity, like (or akin to) an animal: "Man's bestiality to man"
- (dated) Any abstract entity similar to a beast.
Related terms 
status of animal