pepperwort vs clover fern

pepperwort and clover fern both are nouns.

Word	Noun	Adjective	Verb	Adverb
pepperwort	Yes	No	No	No
clover fern	Yes	No	No	No

As nouns, pepperwort and clover fern are synonyms defined as:

pepperwort and clover fern: any of several water ferns of the genus Marsilea having four leaflets

pepperwort (noun)	clover fern (noun)
annual herb used as salad green and garnish	any of several water ferns of the genus Marsilea having four leaflets
any of several water ferns of the genus Marsilea having four leaflets