The Collaborative International Dictionary of English v.0.48:

Supplant \Sup*plant"\, v. t. [imp. & p. p. Supplanted; p. pr.
   & vb. n. Supplanting.] [F. supplanter, L. supplantare to
   trip up one's heels, to throw down; sub under + planta the
   sole of the foot, also, a sucker, slip, sprout. Cf. Plant,
   n.]
   1. To trip up. [Obs.] "Supplanted, down he fell." --Milton.
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   2. To displace and take the place of; to supersede; to remove
      or displace by stratagem; as, a rival supplants another in
      the favor of a mistress or a prince.
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            Suspecting that the courtier had supplanted the
            friend.                               --Bp. Fell.
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   3. To overthrow, undermine, or force away, in order to get a
      substitute in place of. [obsolescent]
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            You never will supplant the received ideas of God.
                                                  --Landor.
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   4. To remove (a thing) and replace it with something else.
      [PJC]

   Syn: To remove; displace; overpower; undermine; overthrow;
        supersede.
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