The Collaborative International Dictionary of English v.0.48:

Disoblige \Dis`o*blige"\, v. t. [imp. & p. p. Disobliged; p.
   pr. & vb. n. Disobliging.] [Pref. dis- + oblige: cf. F.
   d['e]sobliger.]
   1. To do an act which contravenes the will or desires of; to
      offend by an act of unkindness or incivility; to
      displease; to refrain from obliging; to be unaccommodating
      to.
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            Those . . . who slight and disoblige their friends,
            shall infallibly come to know the value of them by
            having none when they shall most need them. --South.
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            My plan has given offense to some gentlemen, whom it
            would not be very safe to disoblige.  --Addison.
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   2. To release from obligation. [Obs.]
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            Absolving and disobliging from a more general
            command for some just and reasonable cause.
                                                  --Milton.
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