1. someone who claims to speak the truth; "a bold asserter"; "a declarer of his intentions"; "affirmers of traditional doctrine"; "an asseverator of strong convictions"; "an avower of his own great intelligence"

(synonym) asserter , declarer , asseverator , avower

(hypernym) communicator

(hyponym) postulator

(derivation) affirm , verify , assert , avow , aver , swan , swear