An umpire is an official who enforces the rules during a game or sporting event. In baseball, the umpire stands behind home plate and near the bases, calling balls and strikes, deciding whether runners are safe or out, and making sure both teams follow the rules. In tennis, the umpire sits in a tall chair beside the court, tracking the score and settling disputes about whether balls landed in or out.

The job requires sharp eyes, quick decisions, and the courage to make calls even when players and fans disagree loudly. A good umpire stays calm and fair, treating both teams equally no matter how much pressure they face. When a close play happens, like a runner sliding into second base just as the ball arrives, the umpire must decide instantly: safe or out? There's no time to hesitate, and people usually accept that the umpire's call is final.

Unlike a referee (who often runs up and down a basketball court or soccer field), an umpire typically stays in one position. The word can also be used as a verb: someone might umpire a Little League game on Saturday morning. While the calls aren't always popular, sports couldn't function without someone keeping the game fair and orderly.