|—n , pl -na, -nums|
|1.||Nontechnical name: breastbone (in man) a long flat vertical bone, situated in front of the thorax, to which are attached the collarbone and the first seven pairs of ribs|
|2.||the corresponding part in many other vertebrates|
|3.||Compare tergum a cuticular plate covering the ventral surface of a body segment of an arthropod|
|[C17: via New Latin from Greek sternon breastbone]|
sternum ster·num (stûr'nəm)
n. pl. ster·nums or ster·na (-nə)
A long flat bone, articulating with the cartilages of the first seven ribs and with the clavicle, forming the middle part of the anterior wall of the thorax, and consisting of the corpus, manubrium, and xiphoid process. Also called breastbone.
in the anatomy of tetrapods (four-limbed vertebrates), elongated bone in the centre of the chest that articulates with and provides support for the clavicles (collarbones) of the shoulder girdle and for the ribs. Its origin in evolution is unclear. A sternum appears in certain salamanders; it is present in most other tetrapods but lacking in legless lizards, snakes, and turtles (in which the shell provides needed support). In birds an enlarged keel develops, to which flight muscles are attached; the sternum of the bat is also keeled as an adaptation for flight
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