n. A person to whose sole decision a controversy or question between parties is referred; one agreed upon as a judge, arbiter, or referee in case of conflict of opinions; specifically, a person selected to see that the rules of a game, as cricket or base-ball, are enforced, and to decide disputed or debatable points.n. In law, a third person called in to decide a controversy or question submitted to arbitrators when the arbitrators do not agree in opinion.To decide as umpire; settle, as a dispute. Specifically To enforce the rules of (a game), and decide disputed points: as, to umpire a game of baseball.To act as umpire.