wild oat grass vs Avena fatua

wild oat grass and Avena fatua both are nouns.

Word	Noun	Adjective	Verb	Adverb
wild oat grass	Yes	No	No	No
Avena fatua	Yes	No	No	No

As nouns, wild oat grass and Avena fatua are synonyms defined as:

Other synonyms of wild oat grass include wild oat.

wild oat grass (noun)	Avena fatua (noun)
common in meadows and pastures	common in meadows and pastures