cob vs edible nut

cob and edible nut both are nouns.

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

As nouns, edible nut is a hypernym of cob; that is, edible nut is a word with a broader meaning than cob:

cob: nut of any of several trees of the genus Corylus
edible nut: a hard-shelled seed consisting of an edible kernel or meat enclosed in a woody or leathery shell

cob (noun)	edible nut (noun)
adult male swan	a hard-shelled seed consisting of an edible kernel or meat enclosed in a woody or leathery shell
stocky short-legged harness horse
white gull having a black back and wings
nut of any of several trees of the genus Corylus