bargainer vs fishwife

bargainer and fishwife both are nouns.

Word	Noun	Adjective	Verb	Adverb
bargainer	Yes	No	No	No
fishwife	Yes	No	No	No

As nouns, fishwife is a hyponym of bargainer; that is, fishwife is a word with a more specific, narrower meaning than bargainer:

bargainer: someone who purchases and maintains an inventory of goods to be sold
fishwife: someone who sells fish

bargainer (noun)	fishwife (noun)
someone who purchases and maintains an inventory of goods to be sold	someone who sells fish
negotiator of the terms of a transaction