chiropteran vs megabat

chiropteran and megabat both are nouns.

Word	Noun	Adjective	Verb	Adverb
chiropteran	Yes	No	No	No
megabat	Yes	No	No	No

As nouns, megabat is a hyponym of chiropteran; that is, megabat is a word with a more specific, narrower meaning than chiropteran:

chiropteran: nocturnal mouselike mammal with forelimbs modified to form membranous wings and anatomical adaptations for echolocation by which they navigate
megabat: large Old World bat of warm and tropical regions that feeds on fruit

Other hyponyms of chiropteran include fruit bat, carnivorous bat, microbat.

chiropteran (noun)	megabat (noun)
nocturnal mouselike mammal with forelimbs modified to form membranous wings and anatomical adaptations for echolocation by which they navigate	large Old World bat of warm and tropical regions that feeds on fruit