The Collaborative International Dictionary of English v.0.48:
Interpose \In`ter*pose"\, v. t. [imp. & p. p. Interposed; p.
   pr. & vb. n. Interposing.] [F. interposer. See Inter-,
   and Pose, v. t.]
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   1. To place between; as, to interpose a screen between the
      eye and the light.
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            Mountains interposed
            Make enemies of nations.              --Cowper.
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   2. To thrust; to intrude; to put between, either for aid or
      for troubling.
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            What watchful cares do interpose themselves
            Betwixt your eyes and night?          --Shak.
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            The common Father of mankind seasonably interposed
            his hand, and rescues miserable man.  --Woodward.
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   3. To introduce or inject between the parts of a conversation
      or argument. --Milton.
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