The Collaborative International Dictionary of English v.0.48:

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.
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         Hatred unto the truth did always falsely report and
         calumniate all godly men's doings.       --Strype.
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   Syn. -- To asperse; slander; defame; vilify; traduce;
      belie; bespatter; blacken; libel. See Asperse.
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