Muscle that moves arm toward the mid-line.

There are two motions which takes place within the coronal plane involving the medial-lateral motions of the limbs, fingers, toes, or thumb. These motions are known as adduction and abduction motions. Abduction helps to raise the arm at the shoulder joint, moving it laterally away from the body while adduction helps the  arm down to the side of the body. Hence, we can say that abduction moves the limb laterally away from the mid-line of the body, while adduction is the opposing movement that brings the limb toward the body or across the mid-line.