The Collaborative International Dictionary of English v.0.48:

Vulva \Vul"va\, n. [L. vulva, volva, from volvere to roll.]
   [1913 Webster]
   1. (Anat.) The external parts of the female genital organs;
      sometimes, the opening between the projecting parts of the
      external organs.
      [1913 Webster]

   2. (Zool.) The orifice of the oviduct of an insect or other
      invertebrate.
      [1913 Webster]

WordNet (r) 3.0 (2006):

vulva
    n 1: external parts of the female genitalia