A hitter is someone who hits, but the word's meaning changes dramatically depending on the context.

In baseball, a hitter is a batter, the player who stands at home plate trying to hit the ball with a bat. Teams want good hitters who can consistently make contact and get on base. Some hitters are known for power (hitting home runs), while others excel at precision (placing the ball exactly where defenders aren't). When commentators say a player is a “career .300 hitter,” they mean that player gets a hit about 30% of the time they're at bat, which is excellent.

The word can describe anyone who strikes or hits things: a heavy hitter in boxing lands powerful punches, while in business, a heavy hitter is an influential person who makes big deals happen. A pinch hitter in baseball comes off the bench to bat for another player in a crucial moment, and people use this phrase in everyday life too: if your teacher is sick, a substitute becomes the pinch hitter for the day.