mastiff bat

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various snub-nosed bats of the family Molossidae, found in warm regions of most parts of the world and having narrow wings and brown, gray, or black fur.

Century Dictionary and Cyclopedia

1. n. A molossoid or bulldog-bat; a member of the Molossinæ: so called from its physiognomy. See Molossinæ.

GNU Webster's 1913

1. n. (Zoöl.) , any bat of the genus Molossus; so called because the face somewhat resembles that of a mastiff.

WordNet 3.0

1. n. a soft-furred chocolate-brown bat with folded ears and small wings; often runs along the ground