genus Castanea vs chestnut

genus Castanea and chestnut both are nouns.

Word	Noun	Adjective	Verb	Adverb
genus Castanea	Yes	No	No	No
chestnut	Yes	Yes	No	No

genus Castanea (noun)	chestnut (noun)
chestnuts; chinkapins	a dark golden-brown or reddish-brown horse
	a small horny callus on the inner surface of a horse's leg
	the brown color of chestnuts
	edible nut of any of various chestnut trees of the genus Castanea
	any of several attractive deciduous trees yellow-brown in autumn; yield a hard wood and edible nuts in a prickly bur
	wood of any of various chestnut trees of the genus Castanea

genus Castanea (adjective)	chestnut (adjective)
	(of hair or feathers) of a golden brown to reddish brown color