What is Referee?

Legal Definition
A referee or simply ref is the person of authority in a variety of sports who is responsible for presiding over the game from a neutral point of view and making on-the-fly decisions that enforce the rules of the sport, including sportsmanship decisions such as ejection. The official tasked with this job may be known, in addition to referee, by a variety of other titles as well (often depending on the sport), including umpire, judge, arbiter, arbitrator, linesman, commissaire, timekeeper, touch judge or Technical Official (by the International Olympic Committee).
-- Wikipedia
Legal Definition
A person to whom has been referred a matter in dispute, in order that he may settle it. His judgment is called an award. Vide Arbitrator; Reference.
-- Bouviers Law Dictionary
Legal Definition
In practice. A person to whom a cause pending in a court is referred by the court, to take testimony, hear the parties, and report thereon to the court See Reter. And see In re Hathaway, 71 N. Y. 243; Betts v. Letcher, 1 S. D. 182, 46 N. W. 193; Central Trust Co. v. Wabash, etc., R. Co. (C. C.) 32 Fed. 685. See Referee in bankruptcy.
-- Black's Law Dictionary
Legal Definition
An officer of the court appointed for a specific purpose, as to take testimony. See 1 S. D. 182, 46 N. W. 193.
-- Ballentine's Law Dictionary