edible nut vs butternut

edible nut and butternut both are nouns.

Word	Noun	Adjective	Verb	Adverb
edible nut	Yes	No	No	No
butternut	Yes	No	No	No

As nouns, butternut is a hyponym of edible nut; that is, butternut is a word with a more specific, narrower meaning than edible nut:

edible nut: a hard-shelled seed consisting of an edible kernel or meat enclosed in a woody or leathery shell
butternut: oily egg-shaped nut of an American tree of the walnut family

edible nut (noun)	butternut (noun)
a hard-shelled seed consisting of an edible kernel or meat enclosed in a woody or leathery shell	oily egg-shaped nut of an American tree of the walnut family
	North American walnut tree having light-brown wood and edible nuts; source of a light-brown dye