Definition of Collarbone

Collarbone: A horizontal bone above the first rib that makes up the front part of the shoulder.

The collarbone, also called the "clavicle," links the sternum, or breastbone, with the scapula, a triangular bone in the back of the shoulder.

The collarbone ends at the sternum, forming one side of the sternoclavicular joint. It ends at the shoulder, there forming one side of the acromioclavicular joint.