voxel

from The Free On-line Dictionary of Computing (8 July 2008)

voxel

   <jargon> (By analogy with "{pixel}") Volume element.

   The smallest distinguishable box-shaped part of a
   three-dimensional space.  A particular voxel will be
   identified by the x, y and z coordinates of one of its eight
   corners, or perhaps its centre.  The term is used in three
   dimensional modelling.

   (1995-03-10)