Umpire

Umpire, the term used, like "referee," for a person appointed by consent to settle disputes arising between opposing parties, and particularly one chosen to see that the rules of a game are obeyed. The word itself stands for the Middle English nompere  or noumpere, " a numpere" becoming "an umpire." The earlier form represents the Old French nompere, nonpair, i.e. not equal, odd. The Latin impar, unequal, was similarly used in the sense of "arbitrator."