Clavicle :: Clavicle (n.) The collar bone, which is joined at one end to the scapula, or shoulder blade, and at the other to the sternum, or breastbone. In man each clavicle is shaped like the letter /, and is situated just above the first rib on either side of the neck. In birds the two clavicles are united ventrally, forming the merrythought, or wishbone..