water bitternut vs hickory

water bitternut and hickory both are nouns.

Word	Noun	Adjective	Verb	Adverb
water bitternut	Yes	No	No	No
hickory	Yes	No	No	No

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

water bitternut: hickory of southern United States having many narrow leaflets and rather bitter nuts
hickory: American hardwood tree bearing edible nuts

Other hypernyms of water bitternut include hickory tree.

water bitternut (noun)	hickory (noun)
hickory of southern United States having many narrow leaflets and rather bitter nuts	American hardwood tree bearing edible nuts
	valuable tough heavy hardwood from various hickory trees