edible nut vs pignolia

edible nut and pignolia both are nouns.

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

As nouns, pignolia is a hyponym of edible nut; that is, pignolia 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
pignolia: edible seed of any of several nut pines especially some pinons of southwestern North America

edible nut (noun)	pignolia (noun)
a hard-shelled seed consisting of an edible kernel or meat enclosed in a woody or leathery shell	edible seed of any of several nut pines especially some pinons of southwestern North America