Noun | 1. | ![]() glenoid cavity, glenoid fossa - the concavity in the head of the scapula that receives the head of the humerus to form the shoulder joint acromial process, acromion - the outermost point of the spine of the shoulder blade articulatio humeri, shoulder joint, shoulder - a ball-and-socket joint between the head of the humerus and a cavity of the scapula endoskeleton - the internal skeleton; bony and cartilaginous structure (especially of vertebrates) |