Labellum (l&adot_;b&ebreve_;llŭm), n.; pl. L. Labella (l&adot_;b&ebreve_;ll&adot_;), E. Labellums (l&adot_;b&ebreve_;llŭmz). [L., dim. of labrum lip.] 1. (Bot.) The lower or apparently anterior petal of an orchidaceous flower, often of a very curious shape.[1913 Webster]
2. (Zoöl.) A small appendage beneath the upper lip or labrum of certain insects.[1913 Webster]