Poaceae vs family Gramineae

Poaceae and family Gramineae both are nouns.

Word	Noun	Adjective	Verb	Adverb
Poaceae	Yes	No	No	No
family Gramineae	Yes	No	No	No

As nouns, Poaceae and family Gramineae are synonyms defined as:

Poaceae and family Gramineae: the grasses: chiefly herbaceous but some woody plants including cereals, bamboo, reeds, sugar cane

Other synonyms of Poaceae include family Graminaceae, family Poaceae, Graminaceae, Gramineae, grass family.

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