smut grass vs carpet grass

smut grass and carpet grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
smut grass	Yes	No	No	No
carpet grass	Yes	No	No	No

As nouns, smut grass and carpet grass are synonyms defined as:

smut grass and carpet grass: grass native to West Indies but common in southern United States having tufted wiry stems often infested with a dark fungus

Other synonyms of smut grass include blackseed, Sporobolus poiretii.

smut grass (noun)	carpet grass (noun)
grass native to West Indies but common in southern United States having tufted wiry stems often infested with a dark fungus	grass native to West Indies but common in southern United States having tufted wiry stems often infested with a dark fungus