Synonyms of arbiter

1. arbiter, supreme authority, expert: usage: someone with the power to settle matters at will; "she was the final arbiter on all matters of fashion"
2. arbiter, arbitrator, umpire, evaluator, judge: usage: someone chosen to judge and decide a disputed issue; "the critic was considered to be an arbiter of modern literature"; "the arbitrator's authority derived from the consent of the disputants"; "an umpire was appointed to settle the tax case"