Source : Webster's Revised Unabridged Dictionary (1913)

Calumniate \Ca*lum"ni*ate\, v. i. [imp. & p. p. {Calumniated};
   p. pr. & vb. n. {calumniating}.] [L. calumniatus, p. p. of
   calumniari. See {Calumny}, and cf. {Challenge}, v. t.]
   To accuse falsely and maliciously of a crime or offense, or
   of something disreputable; to slander; to libel.

         Hatred unto the truth did always falsely report and
         calumniate all godly men's doings.       --Strype.

   {Syn}. -- To asperse; slander; defame; vilify; traduce;
      belie; bespatter; blacken; libel. See {Asperse}.

Calumniate \Ca*lum"ni*ate\, v. i.
   To propagate evil reports with a design to injure the
   reputation of another; to make purposely false charges of
   some offense or crime.

Source : WordNet®

calumniate
     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: {defame}, {slander}, {smirch}, {asperse},
          {denigrate}, {smear}, {sully}, {besmirch}]