Labellum \La*bel"lum\, n.; pl. L. {Labella}, E. {Labellums}.
[L., dim. of labrum lip.]
1. (Bot.) The lower or apparently anterior petal of an
orchidaceous flower, often of a very curious shape.
2. (Zo["o]l.) A small appendage beneath the upper lip or
labrum of certain insects.