arbiter, supreme authority -- (someone with the power to settle matters at will; "she was the final arbiter on all matters of fashion")
arbiter, arbitrator, umpire -- (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")
(Sound)
