n. any of several straight muscles. The rectus muscles of the orbit are some of the extrinsic eye muscles. Rectus abdominis is a long flat muscle that extends bilaterally along the entire length of the front of the abdomen. The rectus muscles acting together serve to bend the trunk forwards; acting separately they bend the body sideways. The rectus femoris forms part of the quadriceps.
Subjects: Medicine and Health — Psychology.