sea purse vs undertow

sea purse and undertow both are nouns.

Word	Noun	Adjective	Verb	Adverb
sea purse	Yes	No	No	No
undertow	Yes	No	No	No

As nouns, sea purse and undertow are synonyms defined as:

sea purse and undertow: the seaward undercurrent created after waves have broken on the shore

Other synonyms of sea purse include sea-poose, sea-purse, sea-puss, sea puss.

sea purse (noun)	undertow (noun)
the seaward undercurrent created after waves have broken on the shore	the seaward undercurrent created after waves have broken on the shore
	an inclination contrary to the strongest or prevailing feeling