The Collaborative International Dictionary of English v.0.48:

Obligate \Ob"li*gate\, v. t. [imp. & p. p. Obligated; p. pr. &
   vb. n. Obligating.] [L. obligatus, p. p. of obligare. See
   Oblige.]
   1. To bring or place under obligation, moral or legal; to
      hold by a constraining motive. "Obligated by a sense of
      duty." --Proudfit.
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            That's your true plan -- to obligate
            The present ministers of state.       --Churchill.
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   2. To bind or firmly hold to an act; to compel; to constrain;
      to bind to any act of duty or courtesy by a formal pledge.
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            That they may not incline or be obligated to any
            vile or lowly occupations.            --Landor.
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