Cyperus rotundus vs nut grass

Cyperus rotundus and nut grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cyperus rotundus	Yes	No	No	No
nut grass	Yes	No	No	No

As nouns, Cyperus rotundus and nut grass are synonyms defined as:

Cyperus rotundus and nut grass: a widely distributed perennial sedge having small edible nutlike tubers

Other synonyms of Cyperus rotundus include nut sedge, nutgrass, nutsedge.

Cyperus rotundus (noun)	nut grass (noun)
a widely distributed perennial sedge having small edible nutlike tubers	a widely distributed perennial sedge having small edible nutlike tubers