umpire (baseball)

In baseball, the umpire is the person charged with officiating the game, including beginning and ending the game, enforcing the rules of the game and the grounds, making judgment calls on plays, and meting out discipline. The term is often shortened to the colloquial form ump. They are also sometimes addressed as blue due to the color of the uniform some umpires wear. Although games were often officiated by a sole umpire in the formative years of the sport, from the turn of the 20th century onward officiating has been commonly divided among several umpires, who form the umpiring crew.
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