Source : Webster's Revised Unabridged Dictionary (1913)

Warranter \War"rant*er\, n.
   1. One who warrants, gives authority, or legally empowers.

   2. (Law) One who assures, or covenants to assure; one who
      contracts to secure another in a right, or to make good
      any defect of title or quality; one who gives a warranty;
      a guarantor; as, the warranter of a horse.

Source : WordNet®

warranter
     n : one who provides a warrant or guarantee to another [syn: {guarantor},
          {surety}, {warrantor}]