Source : Webster's Revised Unabridged Dictionary (1913)

Synergistic \Syn`er*gis"tic\, a.
   1. Of or pertaining to synergism. ``A synergistic view of
      regeneration.'' --Shedd.

   2. Co["o]perating; synergetic.

Source : WordNet®

synergistic
     adj 1: used especially of drugs or muscles that work together so
            the total effect is greater than the sum of the two
            (or more) [syn: {interactive}] [ant: {antagonistic}]
     2: of or relating to the theological doctrine of synergism
     3: working together; used especially of groups, as subsidiaries
        of a corporation, cooperating for an enhanced effect; "a
        synergistic effect" [syn: {synergetic}]