black walnut tree vs black hickory

black walnut tree and black hickory both are nouns.

Word	Noun	Adjective	Verb	Adverb
black walnut tree	Yes	No	No	No
black hickory	Yes	No	No	No

As nouns, black walnut tree and black hickory are synonyms defined as:

black walnut tree and black hickory: North American walnut tree with hard dark wood and edible nut

Other synonyms of black walnut tree include black walnut, Juglans nigra.

black walnut tree (noun)	black hickory (noun)
North American walnut tree with hard dark wood and edible nut	an American hickory tree having bitter nuts
	smooth-barked North American hickory with 7 to 9 leaflets bearing a hard-shelled edible nut
	North American walnut tree with hard dark wood and edible nut