plural noun

Definition of Vespertilionidae

: a very large family of bats (suborder Microchiroptera) found in most parts of the world, including the majority of the common bats of temperate regions, and having separate ears with well-developed tragal lobes, a simple nose without appendages, and a tail that extends to the border of the posterior part of the volar membrane which stretches between the thighs — see vespertilio

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History and Etymology for Vespertilionidae

New Latin, from Vespertilion-, Vespertilio, type genus + -idae

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formidable, illustrious, or eminent

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