councilwoman vs councillor

councilwoman and councillor both are nouns.

Word	Noun	Adjective	Verb	Adverb
councilwoman	Yes	No	No	No
councillor	Yes	No	No	No

As nouns, councillor is a hypernym of councilwoman; that is, councillor is a word with a broader meaning than councilwoman:

Other hypernyms of councilwoman include council member, adult female, woman.

councilwoman (noun)	councillor (noun)
a woman who is a council member	a member of a council