The Collaborative International Dictionary of English v.0.48:
Vespertilio \Ves`per*til"i*o\, n. [L., a bat.] (Zool.) A genus of bats including some of the common small insectivorous species of North America and Europe. [1913 Webster]WordNet (r) 3.0 (2006):
Vespertilio n 1: a genus of Vespertilionidae [syn: Vespertilio, genus Vespertilio]