LABRUM

‖La″brum (?), n.; pl. L. Labra (#), E. Labrums (#). [] 1. 1. A lip or edge, as of a basin.
2. 2. (Zoöl.) (a) An organ in insects and crustaceans covering the upper part of the mouth, and serving as an upper lip. See Illust. of Hymenoptera. (b) The external margin of the aperture of a shell. See Univalve.