For the muscle of the neck, see Rectus capitis lateralis muscle

The lateral rectus muscle is a muscle on the lateral side of the eyeball in the orbit. It is one of six extraocular muscles that control the movements of the eye. The lateral rectus muscle is responsible for lateral movement of the eyeball, specifically abduction. Abduction describes the movement of the eye away from the eyeball, allowing the eyeball to move horizontally in the lateral direction, bringing the pupil away from the midline of the body.