Source : Webster's Revised Unabridged Dictionary (1913)

Obturator \Ob"tu*ra`tor\, n.
   1. (Ordnance) Any device for preventing the escape of gas
      through the breech mechanism of a breech-loading gun; a
      gas check.

   2. (Photog.) A camera shutter.

Obturator \Ob"tu*ra`tor\, n. [NL., fr. L. obturare to stop up:
   cf.F. obturateur.]
   1. That which closes or stops an opening.

   2. (Surg.) An apparatus designed to close an unnatural
      opening, as a fissure of the palate.

Obturator \Ob"tu*ra`tor\, a. (Anat.)
   Serving as an obturator; closing an opening; pertaining to,
   or in the region of, the obturator foramen; as, the obturator
   nerve.

   {Obturator foramen} (Anat.), an opening situated between the
      public and ischial parts of the innominate bone and closed
      by the obturator membrane; the thyroid foramen.

Source : WordNet®

obturator
     n : a prosthesis used to close an opening (as to close an
         opening of the hard palate in cases of cleft palate)