ANATOMY & PHYSIOLOGY A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z                    HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site deltoid Deltoid. Source: Gray's Anatomy The thick triangular muscle of the shoulder region that forms the rounded flesh of the outer part of the upper arm, and passes up and over the shoulder joint. The wide end of the deltoid is attached to the scapula (shoulderblade) and the clavicle (collarbone). The muscle fibers converge to form the apex of the triangle, which is attached to the humerus (upper-arm bone) about halfway down its length. The central, strongest part of the muscle raises the arm sideways. The front and back parts of the muscle twist the arm. Related category    • ANATOMY AND PHYSIOLOGY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP