avower vs affirmer

avower and affirmer both are nouns.

Word	Noun	Adjective	Verb	Adverb
avower	Yes	No	No	No
affirmer	Yes	No	No	No

As nouns, avower and affirmer are synonyms defined as:

Other synonyms of avower include asserter, asseverator, declarer.

avower (noun)	affirmer (noun)
someone who admits or acknowledges openly and boldly	someone who claims to speak the truth
someone who claims to speak the truth