The Collaborative International Dictionary of English v.0.48:

Separator \Sep"a*ra`tor\, n. [L.]
   One who, or that which, separates. Specifically:
   (a) (Steam Boilers) A device for depriving steam of particles
       of water mixed with it.
   (b) (Mining) An apparatus for sorting pulverized ores into
       grades, or separating them from gangue.
   (c) (Weaving) An instrument used for spreading apart the
       threads of the warp in the loom, etc.
       [1913 Webster]

WordNet (r) 3.0 (2006):

separator
    n 1: an apparatus that uses centrifugal force to separate
         particles from a suspension [syn: centrifuge,
         extractor, separator]