The Collaborative International Dictionary of English v.0.48:

Discredit \Dis*cred"it\, v. t. [imp. & p. p. Discredited; p.
   pr. & vb. n. Discrediting.] [Cf. F. discr['e]diter.]
   1. To refuse credence to; not to accept as true; to
      disbelieve; as, the report is discredited.
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   2. To deprive of credibility; to destroy confidence or trust
      in; to cause disbelief in the accuracy or authority of.
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            An occasion might be given to the . . . papists of
            discrediting our common English Bible. --Strype.
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   2. To deprive of credit or good repute; to bring reproach
      upon; to make less reputable; to disgrace.
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            He. . . least discredits his travels who returns the
            same man he went.                     --Sir H.
                                                  Wotton.
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