DICT.TW Dictionary Taiwan

 Um·bo n.; pl. L. Umbones E. Umbos
 1. The boss of a shield, at or near the middle, and usually projecting, sometimes in a sharp spike.
 2. A boss, or rounded elevation, or a corresponding depression, in a palate, disk, or membrane; as, the umbo in the integument of the larvae of echinoderms or in the tympanic membrane of the ear.
 3. Zool. One of the lateral prominences just above the hinge of a bivalve shell.
 ◄ ►