The Collaborative International Dictionary of English v.0.48:

Rebate \Re*bate"\ (r[-e]*b[=a]t"), v. t. [F. rebattre to beat
   again; pref. re- re- + battre to beat, L. batuere to beat,
   strike. See Abate.]
   1. To beat to obtuseness; to deprive of keenness; to blunt;
      to turn back the point of, as a lance used for exercise.
      [1913 Webster]

            But doth rebate and blunt his natural edge. --Shak.
      [1913 Webster]

   2. To deduct from; to make a discount from, as interest due,
      or customs duties. --Blount.
      [1913 Webster]

   3. To return a portion of a sum paid, as a method of
      discounting of prices.
      [PJC]

   Rebated cross, a cross which has the extremities of the
      arms bent back at right angles, as in the fylfot.
      [1913 Webster]