To crouch is to bend your knees, pull your body in, and sit on your heels. This position is called a crouch. You might crouch down to pet a kitten or catch a baseball.
The catcher in baseball stands in a low crouch, waiting for the pitch. Little kids might crouch in a closet or under a table when they play hide and seek. People crouch when they’re in a small space or to keep themselves warm. When you’re in a crouch, your body takes up less space. Crouch comes from the French crochir, "become bent or crooked," after the shape of a hook or a croche.