longan vs fruit tree

longan and fruit tree both are nouns.

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

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

longan: tree of southeastern Asia to Australia grown primarily for its sweet edible fruit resembling litchi nuts; sometimes placed in genera Euphorbia or Nephelium
fruit tree: tree bearing edible fruit

longan (noun)	fruit tree (noun)
tree of southeastern Asia to Australia grown primarily for its sweet edible fruit resembling litchi nuts; sometimes placed in genera Euphorbia or Nephelium	tree bearing edible fruit