Carya ovata vs hickory

Carya ovata and hickory both are nouns.

Word	Noun	Adjective	Verb	Adverb
Carya ovata	Yes	No	No	No
hickory	Yes	No	No	No

As nouns, hickory is a hypernym of Carya ovata; that is, hickory is a word with a broader meaning than Carya ovata:

Carya ovata: North American hickory having loose grey shaggy bark and edible nuts
hickory: American hardwood tree bearing edible nuts

Other hypernyms of Carya ovata include hickory tree.

Carya ovata (noun)	hickory (noun)
North American hickory having loose grey shaggy bark and edible nuts	American hardwood tree bearing edible nuts
	valuable tough heavy hardwood from various hickory trees