Hypertext Webster Gateway: "labia"

From Webster's Revised Unabridged Dictionary (1913) (web1913)

2. The lip of an organ pipe.

3. pl. (Anat.) The folds of integument at the opening of the
vulva.

4. (Zo["o]l.)
(a) The organ of insects which covers the mouth beneath,
and serves as an under lip. It consists of the second
pair of maxill[ae], 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).
(b) Inner margin of the aperture of a shell.

From Webster's Revised Unabridged Dictionary (1913) (web1913)

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