The Collaborative International Dictionary of English v.0.48:

Dualistic \Du`al*is"tic\, a.
   Consisting of two; pertaining to dualism or duality.
   [1913 Webster]

   Dualistic system or Dualistic theory (Chem.), an old
      theory, originated by Lavoisier and developed by
      Berzelius, that all definite compounds are binary in their
      nature, and consist of two distinct constituents,
      themselves simple or complex, and possessed of opposite
      chemical or electrical affinities; -- superseded by later
      developments in chemical bonding theory, especially
      quantum mechanics.
      [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

dualistic
    adj 1: of or relating to the philosophical doctrine of dualism;
           "a Manichaean conflict between good and evil" [syn:
           dualistic, Manichaean]

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "dualistic":
   bifold, biform, bifurcated, bilateral, binary, bipartisan,
   bipartite, dichotomous, double, double-barreled, duadic, dual,
   duple, duplex, duplicated, dyadic, identical, matched, twain, twin,
   twinned, two, two-sided