a. Zool. [ad. mod.L. Vesperlilionid-æ (see def.).] Of or belonging to the Vespertilionidæ, a large family of insectivorous bats, including the common British species.
1875. Dallas, in Cassell’s Nat. Hist., I. 332. The tail traverses the interfemoral membrane in the fashion of that of a Vespertilionid Bat.
