/sterr"neuhm/ , n. , pl. sterna /-neuh/ , sternums .
1. Anat. , Zool. a bone or series of bones extending along the middle line of the ventral portion of the body of most vertebrates, consisting in humans of a flat, narrow bone connected with the clavicles and the true ribs; breastbone. See diag. under skeleton .
2. the ventral surface of a body segment of an arthropod.
[ 1660-70; stérnon chest, breastbone ]