Poaceae vs genus Cenchrus

Poaceae and genus Cenchrus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Poaceae	Yes	No	No	No
genus Cenchrus	Yes	No	No	No

Poaceae (noun)	genus Cenchrus (noun)
the grasses: chiefly herbaceous but some woody plants including cereals, bamboo, reeds, sugar cane	a genus of grasses of the family Gramineae that have burs