Definition of labium in English:

labium

noun

  • 1Biology
    A fused mouthpart which forms the floor of the mouth of an insect.

    • ‘Biplica, in addition, lacks the strongly tubercled and denticulate labium of Eriptycha.’
    • ‘Several groups developed active predatory larvae, still showing the spoon-shaped labium.’
    • ‘Insects close off the posterior of the mouth with a second ‘lip,’ the labium.’
  • 2Botany
    The lower lip of the flower of a plant of the mint family.

Origin

Late 16th century (in the general sense ‘lip, lip-like structure’): from Latin, lip; related to labrum.

Pronunciation:

labium

/ˈleɪbɪəm/