family Gramineae vs genus Avena

family Gramineae and genus Avena both are nouns.

Word	Noun	Adjective	Verb	Adverb
family Gramineae	Yes	No	No	No
genus Avena	Yes	No	No	No

family Gramineae (noun)	genus Avena (noun)
the grasses: chiefly herbaceous but some woody plants including cereals, bamboo, reeds, sugar cane	oats