Source : Webster's Revised Unabridged Dictionary (1913)

Warrant \War"rant\, v. t. [imp. & p. p. {Warranted}; p. pr. &
   vb. n. {Warranting}.] [OE. waranten, OF. warantir, garantir,
   guarantir, garentir, garandir, F. garantir to warrant, fr.
   OF. warant, garant, guarant, a warrant, a protector, a
   defender, F. garant. [root]142. See {Warrant}, n.]
   1. To make secure; to give assurance against harm; to
      guarantee safety to; to give authority or power to do, or
      forbear to do, anything by which the person authorized is
      secured, or saved harmless, from any loss or damage by his
      action.

            That show I first my body to warrant. --Chaucer.

            I'll warrant him from drowning.       --Shak.

            In a place Less warranted than this, or less secure,
            I can not be.                         --Milton.

   2. To support by authority or proof; to justify; to maintain;
      to sanction; as, reason warrants it.

            True fortitude is seen in great exploits, That
            justice warrants, and that wisdom guides. --Addison.

            How little while it is since he went forth out of
            his study, -- chewing a Hebrew text of Scripture in
            his mouth, I warrant.                 --Hawthorne.

   3. To give a warrant or warranty to; to assure as if by
      giving a warrant to.

            [My neck is] as smooth as silk, I warrant ye. --L'
                                                  Estrange.

   4. (Law)
      (a) To secure to, as a grantee, an estate granted; to
          assure.
      (b) To secure to, as a purchaser of goods, the title to
          the same; to indemnify against loss.
      (c) To secure to, as a purchaser, the quality or quantity
          of the goods sold, as represented. See {Warranty}, n.,
          2.
      (d) To assure, as a thing sold, to the purchaser; that is,
          to engage that the thing is what it appears, or is
          represented, to be, which implies a covenant to make
          good any defect or loss incurred by it.

Source : WordNet®

warranted
     adj : secured by written agreement [syn: {bonded}, {guaranteed}, {secured}]