The Collaborative International Dictionary of English v.0.48:

Rebut \Re*but"\ (r[-e]*b[u^]t"), v. t. [imp. & p. p. Rebutted;
   p. pr. & vb. n. Rebutting.] [OF. rebouter to repulse, drive
   back; pref. re- + bouter to push, thrust. See 1st Butt,
   Boutade.]
   [1913 Webster]
   1. To drive or beat back; to repulse.
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            Who him, rencount'ring fierce, as hawk in flight,
            Perforce rebutted back.               --Spenser.
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   2. (Law) To contradict, meet, or oppose by argument, plea, or
      countervailing proof. --Abbott.
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