nectarine tree vs fruit tree

nectarine tree and fruit tree both are nouns.

Word	Noun	Adjective	Verb	Adverb
nectarine tree	Yes	No	No	No
fruit tree	Yes	No	No	No

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

nectarine tree: variety or mutation of the peach bearing fruit with smooth skin and (usually) yellow flesh
fruit tree: tree bearing edible fruit

nectarine tree (noun)	fruit tree (noun)
variety or mutation of the peach bearing fruit with smooth skin and (usually) yellow flesh	tree bearing edible fruit