scapula /skap″yələ/ , one of the pair of large, flat triangular bones that forms the dorsal part of the shoulder girdle. It has two surfaces, three borders, three angles, and a prominent dorsal spine. The acromion of the scapula forms the summit of the shoulder. The coracoid process, resembling a raven’s beak, accommodates the attachment of various muscles, including the pectoralis minor, and ligaments, including the trapezoid. Also called shoulder blade.