A sidearm is a weapon, usually a pistol or revolver, that's carried at a person's side. The name comes from where it's worn: holstered on a belt at the hip or side of the body, making it easy to reach quickly. Police officers, soldiers, and security guards often carry sidearms as backup weapons while their main weapon (like a rifle) requires both hands.

The word sidearm can also describe a throwing motion where your arm moves parallel to the ground instead of overhead. Picture a frisbee throw: your arm swings out to the side and releases at about shoulder height. Baseball pitchers sometimes throw sidearm, releasing the ball from the side rather than over the top. This unusual angle can make the ball move in tricky ways that batters find harder to hit.

When someone throws sidearm, they're using that distinctive sideways motion. You might throw a ball sidearm when there's a low tree branch in the way, or when you want to skip a stone across water.