sternochondroscapularis

from The Century Dictionary.

• noun A muscle of some mammals, not infrequent in man, arising from the first costal cartilage and the sternum, and inserted into the superior border of the scapula. Also called chondroscapularis, scapulocostalis minor, costoscapularis, subclavius posticus.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun anatomy An inconstant muscle arising from the sternum and the first costal cartilage and extending laterally and backward to the upper border of the scapula.