a person to whose sole decision a controversy or question between parties is referred; especially, one chosen to see that the rules of a game, as cricket, baseball, or the like, are strictly observed.-a third person, who is to decide a controversy or question submitted to arbitrators in case of their disagreement.-to decide as umpire; to arbitrate; to settle, as a dispute.-to perform the duties of umpire in or for; as, to umpire a game.-to act as umpire or arbitrator.