The Collaborative International Dictionary of English v.0.48:

disabuse \dis`a*buse"\, v. t. [imp. & p. p. Disabused; p. pr.
   & vb. n. Disabusing.] [Pref. dis- + abuse; cf. F.
   d['e]sabuser.]
   To set free from mistakes; to undeceive; to disengage from
   fallacy or deception; to set right; -- often used with of;
   as, to disabuse one of his illusions.
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         To undeceive and disabuse the people.    --South.
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         If men are now sufficiently enlightened to disabuse
         themselves or artifice, hypocrisy, and superstition,
         they will consider this event as an era in their
         history.                                 --J. Adams.
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