dissipative

from The Collaborative International Dictionary of English v.0.48

dissipative \dis"si*pa*tive\ (d[i^]s"s[i^]*p[asl]*t[i^]v), a.
   Tending to dissipate.
   [1913 Webster]

   {Dissipative system} (Mech.), an assumed system of matter and
      motions in which forces of friction and resistances of
      other kinds are introduced without regard to the heat or
      other molecular actions which they generate; -- opposed to
      {conservative system}.
      [1913 Webster]