The Collaborative International Dictionary of English v.0.48:
Bestiality \Bes*tial"i*ty\, n. [F. bestialit['e].] 1. The state or quality of being bestial. [1913 Webster] 2. Unnatural connection with a beast. [1913 Webster]WordNet (r) 3.0 (2006):
bestiality n 1: the stupid brutal quality of a beast 2: sexual activity between a person and an animal [syn: bestiality, zooerastia, zooerasty]