The Collaborative International Dictionary of English v.0.48:

Trump \Trump\, v. t. [F. tromper to deceive, in OF., to blow a
   trumpet, se tromper de to mock. See Trump a trumpet.]
   1. To trick, or impose on; to deceive. [Obs.] "To trick or
      trump mankind." --B. Jonson.
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   2. To impose unfairly; to palm off.
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            Authors have been trumped upon us.    --C. Leslie.
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   To trump up, to devise; to collect with unfairness; to
      fabricate; as, to trump up a charge.
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