Sternum \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. [1913 Webster]

Note: 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. [1913 Webster]

2. (Zool.) The ventral part of any one of the somites of an arthropod. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

sternum

Source: WordNet (r) 2.0
 

Sternum \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.

Note: 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. (Zo["o]l.) The ventral part of any one of the somites of an arthropod.

Source: Webster's Revised Unabridged Dictionary (1913)