Pronunciation: (lā'bē-um),[key] —n., —pl.-bi•aPronunciation: (-bē-u).[key] 1. a lip or liplike part.
2. Anat. a. a lip or lip-shaped structure or part.
b. any of the folds of skin bordering the vulva.
3. Bot.the lower lip of a bilabiate corolla.
4. Entomol.the posterior, unpaired member of the mouthparts of an insect, formed by the united second maxillae.