Poaceae vs Gramineae

Poaceae and Gramineae both are nouns.

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

As nouns, Poaceae and Gramineae are synonyms defined as:

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

Poaceae (noun)	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