• WordNet 3.6
    • n labium a liplike structure that bounds a bodily orifice (especially any of the four labiate folds of a woman's vulva)
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Webster's Revised Unabridged Dictionary
    • Labium A lip, or liplike organ.
    • Labium (Zoöl) Inner margin of the aperture of a shell.
    • Labium (Anat) The folds of integument at the opening of the vulva.
    • Labium The lip of an organ pipe.
    • Labium (Zoöl) The organ of insects which covers the mouth beneath, and serves as an under lip. It consists of the second pair of maxillæ, usually closely united in the middle line, but bearing a pair of palpi in most insects. It often consists of a thin anterior part (ligula or palpiger) and a firmer posterior plate (mentum).
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Century Dictionary and Cyclopedia
    • n labium In anatomy and zoology, a lip or lip-like part. Specifically. In anatomy:
    • n labium In bot:
    • n labium The lower or anterior lip of a bilabiate corolla
    • n labium In Isoëtes, a lip-like structure formed by the lower margin of the foveola.
    • n labium [capitalized] A genus of ichneumon-flies, with one small New Guinean species
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Chambers's Twentieth Century Dictionary
    • n Labium a lip or lip-like part:—pl. Lā′bia
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Webster's Revised Unabridged Dictionary
Chambers's Twentieth Century Dictionary
Fr.,—L. labium, labrum, a lip.


In literature:

On the right side of the aperture was an elongated and rounded prominence similar in outline to a labium majus.
"Anomalies and Curiosities of Medicine" by George M. Gould
Labium obcordatum basi corneum angustius apice membranaceum medio emarginatum ciliatum lobo utrinque rotundato.
"Narrative of a Survey of the Intertropical and Western Coasts of Australia] [Volume 2 of 2]" by Phillip Parker King
By stretching, it is stated, a labium can be doubled in its dimensions.
"Studies in the Psychology of Sex, Volume 5 (of 6)" by Havelock Ellis
Anthobian: feeding on flowers; applied to certain lamellicorn Coleoptera in which the labium extends beyond the mentum.
"Explanation of Terms Used in Entomology" by John. B. Smith
But the structure of the tongue itself (labium, l) is most curious.
"Our Common Insects" by Alpheus Spring Packard
At the tip of the labium are the labellae, two little lobes which serve to guide the piercing organs.
"Insects and Diseases" by Rennie W. Doane
The four segmented labium or proboscis encloses the lancet-like maxillae and mandibles.
"Handbook of Medical Entomology" by William Albert Riley
At its lower part is hinged a little oblong piece (labium) which may be moved up and down with a needle.
"Through a Microscope" by Samuel Wells
This second pair of maxillae (or labium) form then the hinder or lower boundary of the mouth.
"Encyclopaedia Britannica, 11th Edition, Volume 13, Slice 4" by Various
Labium externum crassum, reflexum.
"Zoological Illustrations, Volume I" by William Swainson