‖Cos″ta (kŏs″tȧ), n. [L., rib. See Coast.] 1. (Anat.) A rib of an animal or a human being.
2. (Bot.) A rib or vein of a leaf, especially the midrib.
3. (Zoöl.) (a) The anterior rib in the wing of an insect. (b) One of the riblike longitudinal ridges on the exterior of many corals.