Source : Webster's Revised Unabridged Dictionary (1913)

Occipital \Oc*cip"i*tal\, a. [Cf. F. occipital.] (Anat.)
   Of or pertaining to the occiput, or back part of the head, or
   to the occipital bone.

   {Occipital bone} (Anat.), the bone which forms the posterior
      segment of the skull and surrounds the great foramen by
      which the spinal cord leaves the cranium. In the higher
      vertebrates it is usually composed of four bones, which
      become consolidated in the adult.

   {Occipital point} (Anat.), the point of the occiput in the
      mesial plane farthest from the ophryon.

Source : WordNet®

occipital bone
     n : a saucer-shaped membrane bone that forms the back of the
         skull