The Collaborative International Dictionary of English v.0.48:

Accredit \Ac*cred"it\, v. t. [imp. & p. p. Accredited; p. pr.
   & vb. n. Accrediting.] [F. accr['e]diter; [`a] (L. ad) +
   cr['e]dit credit. See Credit.]
   1. To put or bring into credit; to invest with credit or
      authority; to sanction.
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            His censure will . . . accredit his praises.
                                                  --Cowper.
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            These reasons . . . which accredit and fortify mine
            opinion.                              --Shelton.
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   2. To send with letters credential, as an ambassador, envoy,
      or diplomatic agent; to authorize, as a messenger or
      delegate.
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            Beton . . . was accredited to the Court of France.
                                                  --Froude.
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   3. To believe; to credit; to put trust in.
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            The version of early Roman history which was
            accredited in the fifth century.      --Sir G. C.
                                                  Lewis.
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            He accredited and repeated stories of apparitions
            and witchcraft.                       --Southey.
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   4. To credit; to vouch for or consider (some one) as doing
      something, or (something) as belonging to some one.
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   To accredit (one) with (something), to attribute
      something to him; as, Mr. Clay was accredited with these
      views; they accredit him with a wise saying.
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Bouvier's Law Dictionary, Revised 6th Ed (1856):

TO ACCREDIT, international law. The act by which a diplomatic agent is
acknowledged by the government near which he is sent. This at once makes his
public character known, and becomes his protection.