asseverator vs declarer

asseverator and declarer both are nouns.

Word	Noun	Adjective	Verb	Adverb
asseverator	Yes	No	No	No
declarer	Yes	No	No	No

As nouns, asseverator and declarer are synonyms defined as:

Other synonyms of asseverator include affirmer, asserter, avower.

asseverator (noun)	declarer (noun)
someone who claims to speak the truth	the bridge player in contract bridge who wins the bidding and can declare which suit is to be trumps
	someone who claims to speak the truth