The Collaborative International Dictionary of English v.0.48:

Harness \Har"ness\, v. t. [imp. & p. p. Harnessed (-n[e^]st);
   p. pr. & vb. n. Harnessing.] [OE. harneisen; cf. F.
   harnacher, OF. harneschier.]
   1. To dress in armor; to equip with armor for war, as a
      horseman; to array.
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            Harnessed in rugged steel.            --Rowe.
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            A gay dagger,
            Harnessed well and sharp as point of spear.
                                                  --Chaucer.
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   2. Fig.: To equip or furnish for defense. --Dr. H. More.
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   3. To make ready for draught; to equip with harness, as a
      horse. Also used figuratively.
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            Harnessed to some regular profession. --J. C.
                                                  Shairp.
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   Harnessed antelope. (Zool.) See Guib.

   Harnessed moth (Zool.), an American bombycid moth (Arctia
      phalerata of Harris), having, on the fore wings, stripes
      and bands of buff on a black ground.
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WordNet (r) 3.0 (2006):

harnessed
    adj 1: brought under control and put to use; "electricity from
           the harnessed Colorado River"; "the harnessed power of
           the atom"