The Collaborative International Dictionary of English v.0.48:

Dismantle \Dis*man"tle\, v. t. [imp. & p. p. Dismantled; p.
   pr. & vb. n. Dismantling.] [F. d['e]manteler, OF.
   desmanteler; pref: des- (L. dis-) + manteler to cover with a
   cloak, defend, fr. mantel, F. manteau, cloak. See Mantle.]
   1. To strip or deprive of dress; to divest.
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   2. To strip of furniture and equipments, guns, etc.; to
      unrig; to strip of walls or outworks; to break down; as,
      to dismantle a fort, a town, or a ship.
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            A dismantled house, without windows or shutters to
            keep out the rain.                    --Macaulay.
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   3. To disable; to render useless. --Comber.

   Syn: To demo?sh; raze. See Demol?sh.
        [1913 Webster]

WordNet (r) 3.0 (2006):

dismantle
    v 1: tear down so as to make flat with the ground; "The building
         was levelled" [syn: level, raze, rase, dismantle,
         tear down, take down, pull down] [ant: erect, put
         up, raise, rear, set up]
    2: take apart into its constituent pieces [syn: disassemble,
       dismantle, take apart, break up, break apart] [ant:
       assemble, piece, put together, set up, tack, tack
       together]
    3: take off or remove; "strip a wall of its wallpaper" [syn:
       strip, dismantle]