watercress vs cresson

watercress is a noun but cresson is not a noun.

Word	Noun	Adjective	Verb	Adverb
watercress	Yes	Yes	No	No
cresson	No	Yes	No	No

As adjectives, watercress and cresson are synonyms defined as:

watercress and cresson: of a moderate yellow-green color that is greener and deeper than moss green and yellower and darker than pea green

Other synonyms of watercress include cress green.

watercress (noun)	cresson (noun)
cresses that grow in clear ponds and streams
any of several water-loving cresses

watercress (adjective)	cresson (adjective)
of a moderate yellow-green color that is greener and deeper than moss green and yellower and darker than pea green	of a moderate yellow-green color that is greener and deeper than moss green and yellower and darker than pea green