Ster"num (?), n.; pl. L. Sterna (#), E. Sternums (#). [NL., from Gr. , the breast, chest.]
1. Anat.
A plate of cartilage, or a series of bony or cartilaginous plates or segments, in the median line of the pectoral skeleton of most vertebrates above fishes; the breastbone.
The sternum is connected with the ribs or the pectorial girdle, or with both. In man it is a flat bone, broad anteriorly, narrowed behind, and connected with the clavicles and the cartilages of the seven anterior pairs of ribs. In most birds it has a high median keel for the attachment of the muscles of the wings.
2. Zool.
The ventral part of any one of the somites of an arthropod.
© Webster 1913.