Source : Webster's Revised Unabridged Dictionary (1913)

Ruin \Ru"in\, v. t. [imp. & p. p. {Ruined};p. pr. & vb. n.
   {Ruining}.] [Cf. F. ruiner, LL. ruinare. See {Ruin}, n.]
   To bring to ruin; to cause to fall to pieces and decay; to
   make to perish; to bring to destruction; to bring to poverty
   or bankruptcy; to impair seriously; to damage essentially; to
   overthrow.

         this mortal house I'll ruin.             --Shak.

         By thee raised, I ruin all my foes.      --Milton.

         The eyes of other people are the eyes that ruin us.
                                                  --Franklin.

         By the fireside there are old men seated, Seeling
         ruined cities in the ashes.              --Longfellow.

Source : WordNet®

ruining
     n : destruction achieved by wrecking something [syn: {laying
         waste}, {ruin}, {ruination}, {wrecking}]