Source : Webster's Revised Unabridged Dictionary (1913)

Defame \De*fame"\, v. t. [imp. & p. p. {Defamed}; p. pr. & vb.
   n. {Defaming}.] [OE. defamen, diffamen, from F. diffamer, or
   OF. perh. defamer, fr. L. diffamare (cf. defamatus infamous);
   dis- (in this word confused with de) + fama a report. See
   {Fame}.]
   1. To harm or destroy the good fame or reputation of; to
      disgrace; especially, to speak evil of maliciously; to
      dishonor by slanderous reports; to calumniate; to asperse.

   2. To render infamous; to bring into disrepute.

            My guilt thy growing virtues did defame; My
            blackness blotted thy unblemish'd name. --Dryden.

   3. To charge; to accuse. [R.]

            Rebecca is . . . defamed of sorcery practiced on the
            person of a noble knight.             --Sir W.
                                                  Scott.

   Syn: To asperse; slander; calumniate; vilify. See {Asperse}.

Defame \De*fame"\, n.
   Dishonor. [Obs.] --Chaucer.

Source : WordNet®

defame
     v : charge falsely or with malicious intent; attack the good
         name and reputation of someone; "The journalists have
         defamed me!" "The article in the paper sullied my
         reputation" [syn: {slander}, {smirch}, {asperse}, {denigrate},
          {calumniate}, {smear}, {sully}, {besmirch}]