grama vs grama grass

grama and grama grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
grama	Yes	No	No	No
grama grass	Yes	No	No	No

As nouns, grama and grama grass are synonyms defined as:

grama and grama grass: pasture grass of plains of South America and western North America

Other synonyms of grama include gramma, gramma grass.

grama (noun)	grama grass (noun)
pasture grass of plains of South America and western North America	pasture grass of plains of South America and western North America