Definition of: umpire

(um′pīr) noun
1. Law A person called upon to settle a disagreement in opinion between arbitrators.
2. In general, anything by which a question in controversy is settled.
3. In various games, as baseball, a person chosen to enforce the rules of the game, and in case of controversy to settle disputed points. See synonyms under JUDGE.
—v.t. & v.i. ·pired, ·pir·ing To decide as umpire; act as umpire (of or in). [Aphetic alter. of ME noumpere <OF nonper odd, uneven (i.e., third) <non not + per even, equal]