umpire

Short definition from Wiktionary

Noun

1. 1
   An official who presides over a sports match.
2. 2
   An official who presides over a sports match: The official who presides over a tennis match sat on a high chair.
3. 3
   An official who presides over a sports match: One of the two white-coated officials who preside over a cricket match.
4. 4
   An official who presides over a sports match: One of the officials who preside over a baseball game.
5. 5
   An official who presides over a sports match: The official who stands behind the line on the defensive side or next to the referee on the offensive side.
6. 6
   An official who presides over a sports match: A match official on the ground deciding and enforcing the rules during play. As of 2007 the Australian Football League uses three; in the past there were two or just one. The other officials, the goal umpires and boundary umpires, are usually referred to by those phrases.
7. 7
   An official who presides over a sports match: The official who presides over a curling game.
8. 8
   A person who arbitrates between contending parties.

Verb

1. 1
   To act as an umpire in a game.
2. 2
   To decide as an umpire.

Proper noun

1. 1
   An unincorporated community in Howard County, Arkansas, United States, named for the umpire of a baseball game.
2. 2
   An unincorporated community in Wright County, Missouri, United States. Origin of the name unknown.