pepperwort vs pepper grass

pepperwort and pepper grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
pepperwort	Yes	No	No	No
pepper grass	Yes	No	No	No

As nouns, pepperwort and pepper grass are synonyms defined as:

pepperwort and pepper grass: annual herb used as salad green and garnish

Other synonyms of pepperwort include common garden cress, garden pepper cress, Lepidium sativum.

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