Arbitrator

n.	1.	A person, or one of two or more persons, chosen by parties who have a controversy, to determine their differences. See Arbitration.
	2.	One who has the power of deciding or prescribing without control; a ruler; a governor. Though Heaven be shut, And Heaven's high Arbitrators sit secure. - Milton. Masters of their own terms and arbitrators of a peace. - Addison.

Noun

1.

arbitrator - someone chosen to judge and decide a disputed issue Synonyms: arbiter

ARBITRATOR. A private extraordinary judge chosen by the parties who have a matter in dispute, invested with power to decide the same. Arbitrators are so called because they have generally an arbitrary power, there being in common no appeal from their sentences, which are called awards. Vide Caldw. on Arb. Index,. h.t.; Kyd on Awards, Index, h.t. 3 Bouv. Inst. n. 2491.

JP, Justice, arbiter, bencher, broker, connection, contact, critic, go-between, his honor, his lordship, his worship, impartial arbitrator, indicator, interagent, intermediary, intermediate, intermedium, internuncio, interpleader, judge, justice, magistrate, mediator, medium, middleman, moderator, negotiant, negotiator, referee, third party, umpire, unbiased observer