The Collaborative International Dictionary of English v.0.48:

Exonerate \Ex*on"er*ate\, v. t. [imp. & p. p. Exonerated; p.
   pr. & vb. n. Exonerating.] [L. exoneratus, p. p. of
   exonerare to free from a burden; ex out, from onerare to
   load, onus load. See Onerous.]
   1. To unload; to disburden; to discharge. [Obs.]
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            All exonerate themselves into one common duct.
                                                  --Ray.
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   2. To relieve, in a moral sense, as of a charge, obligation,
      or load of blame resting on one; to clear of something
      that lies upon oppresses one, as an accusation or
      imputation; as, to exonerate one's self from blame, or
      from the charge of avarice. --Burke.
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   3. To discharge from duty or obligation, as a bail.

   Syn: To absolve; acquit; exculpate. See Absolve.
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