grass family vs Stenotaphrum

grass family and Stenotaphrum both are nouns.

Word	Noun	Adjective	Verb	Adverb
grass family	Yes	No	No	No
Stenotaphrum	Yes	No	No	No

grass family (noun)	Stenotaphrum (noun)
the grasses: chiefly herbaceous but some woody plants including cereals, bamboo, reeds, sugar cane	lawn grasses