arbiter

n. arbitrator, judge; mediator; person whose opinion or judgement is deemed authoritative

Arbiter may refer to:Arbiter (electronics), in computing and electronics a circuitry componentArbiter (Halo), a character in the Halo video game seriesArbitration, in law a method of dispute resolutionHMS Arbiter (D31), an escort aircraft carrier in the Royal Navy of the United KingdomReferee in sporting matchesInternational Arbiter, in chess a title conferred by FIDE to match refereesMemory arbiter, in computing a computer hardware management and synchronization componentWavefront arbiter, a commercial memory arbiter optimized for high-speed operationPetronius, a Roman author and satirist known formally as Gaius Petronius ArbiterArbiter-class starships, Protoss support vessels in the StarCraft science-fiction series.
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Noun
1. someone with the power to settle matters at will; "she was the final arbiter on all matters of fashion"
(synonym) supreme authority
(hypernym) expert
2. someone chosen to judge and decide a disputed issue
(synonym) arbitrator
(hypernym) mediator, go-between, intermediator, intermediary, intercessor
(hyponym) third party
(derivation) intercede, mediate, intermediate, liaise, arbitrate

n. arbitrator (Law); umpire, referee (Sports)

(v. t.)
To act as arbiter between.
  

(n.)
Any person who has the power of judging and determining, or ordaining, without control; one whose power of deciding and governing is not limited.
  

(n.)
A person appointed, or chosen, by parties to determine a controversy between them.