cherimoya tree vs custard apple

cherimoya tree and custard apple both are nouns.

Word	Noun	Adjective	Verb	Adverb
cherimoya tree	Yes	No	No	No
custard apple	Yes	No	No	No

As nouns, custard apple is a hypernym of cherimoya tree; that is, custard apple is a word with a broader meaning than cherimoya tree:

cherimoya tree: small tropical American tree bearing round or oblong fruit
custard apple: any of several tropical American trees bearing fruit with soft edible pulp

Other hypernyms of cherimoya tree include custard apple tree.

cherimoya tree (noun)	custard apple (noun)
small tropical American tree bearing round or oblong fruit	the fruit of any of several tropical American trees of the genus Annona having soft edible pulp
	any of several tropical American trees bearing fruit with soft edible pulp