labrum

A lip or liplike structure, such as the one forming the roof of the mouth in insects.

The outer margin of the opening of a gastropod shell.

In Rom. archæol., a bath-tub, especially one of those of hard, fine material more or loss richly sculptured, rather common in the museums of Italy. Also called lavabrum.

In zoöl, alip or lip-like part. Specifically

A lip or edge, as of a basin.

An organ in insects and crustaceans covering the upper part of the mouth, and serving as an upper lip. See Illust. of Hymenoptera.

The external margin of the aperture of a shell. See Univalve.

A large basin of warm water, with an overhanging lip, in a Roman bath.

The uppermost of the mouthparts (trophi) of a typical insect, such as a cockroach. Typically resembles an upper lip and forms part of the roof of the mouth in such insects.