sweet flag vs Acorus calamus

sweet flag and Acorus calamus both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweet flag	Yes	No	No	No
Acorus calamus	Yes	No	No	No

As nouns, sweet flag and Acorus calamus are synonyms defined as:

sweet flag and Acorus calamus: perennial marsh plant having swordlike leaves and aromatic roots

Other synonyms of sweet flag include calamus, flagroot, myrtle flag, sweet calamus.

sweet flag (noun)	Acorus calamus (noun)
perennial marsh plant having swordlike leaves and aromatic roots	perennial marsh plant having swordlike leaves and aromatic roots