a name applied to various marine univalve shells; esp. to those of the genus strombus, which are of large size. s. gigas is the large pink west indian conch. the large king, queen, and cameo conchs are of the genus cassis. see cameo.-in works of art, the shell used by tritons as a trumpet.-one of the white natives of the bahama islands or one of their descendants in the florida keys; -- so called from the commonness of the conch there, or because they use it for food.-see concha, n.-the external ear. see concha, n., 2.