pl. -·nums or -·na
the thin, flat structure of bone and cartilage to which most of the ribs are attached in the front of the chest in most vertebrates; breastbone
Origin of sternumModern Latin ; from Classical Greek sternon, the breastbone ; from Indo-European base an unverified form ster-, to spread out, strew
nounpl. ster·nums or ster·na
- A long flat bone in most vertebrates that is situated along the ventral midline of the thorax and articulates with the ribs. The manubrium of the sternum articulates with the clavicles in humans and certain other vertebrates. Also called breastbone.
- The ventral portion of a body segment of an arthropod.
Origin of sternumNew Latin, from Greek sternon, breast, breastbone; see ster-2 in Indo-European roots.
(plural sterna or sternums)
- The breastbone.