DECLARER
asserter, declarer, affirmer, asseverator, avower
(noun) 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”
contractor, declarer
(noun) the bridge player in contract bridge who wins the bidding and can declare which suit is to be trumps
Source: WordNet® 3.1
Etymology
Noun
declarer (plural declarers)
(bridge) The person who wins the bidding and so declares what suit will be trump.
One who declares.
(computer science) A statement that declares the properties of a variable or contributes to doing so.
Source: Wiktionary
De*clar"er, n.
Definition: One who makes known or proclaims; that which exhibits. Udall.
Source: Webster’s Unabridged Dictionary 1913 Edition