Up has many and diverse uses in baseball. They include:

• "Batter up!": the umpire's cry starting an inning.

• At bat, at the plate. A player who is at bat is "up" or "up at bat."

• Three up, three down: three batters came to the plate, and all three are out.

• A team in the lead is "up" by some number of runs.

• The batter got under the ball and popped it up.

• The pitcher got the pitch "up", and the batter popped it over the fence for a homer.

• Called up, a player has been promoted from the minors to the majors.