labellum

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

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