Source : Webster's Revised Unabridged Dictionary (1913)

Trump \Trump\, n. [A corruption of triumph, F. triomphe. See
   {Triumph}, and cf. {Trump} a trumpet.]
   1. A winning card; one of a particular suit (usually
      determined by chance for each deal) any card of which
      takes any card of the other suits.

   2. An old game with cards, nearly the same as whist; --
      called also {ruff}. --Decker.

   3. A good fellow; an excellent person. [Slang]

            Alfred is a trump, I think you say.   --Thackeray.

   {To put to one's trumps}, or {To put on one's trumps}, to
      force to the last expedient, or to the utmost exertion.

            But when kings come so low as to fawn upon
            philosophy, which before they neither valued nor
            understood, it is a sign that fails not, they are
            then put to their last trump.         --Milton.

            Put the housekeeper to her trumps to accommodate
            them.                                 --W. Irving.