harpy vs fruit bat

harpy and fruit bat both are nouns.

Word	Noun	Adjective	Verb	Adverb
harpy	Yes	No	No	No
fruit bat	Yes	No	No	No

As nouns, fruit bat is a hypernym of harpy; that is, fruit bat is a word with a broader meaning than harpy:

harpy: any of various fruit bats of the genus Nyctimene distinguished by nostrils drawn out into diverging tubes
fruit bat: large Old World bat of warm and tropical regions that feeds on fruit

Other hypernyms of harpy include megabat.

harpy (noun)	fruit bat (noun)
large black-and-white crested eagle of tropical America	large Old World bat of warm and tropical regions that feeds on fruit
any of various fruit bats of the genus Nyctimene distinguished by nostrils drawn out into diverging tubes
a malicious woman with a fierce temper