The Collaborative International Dictionary of English v.0.48:

Prize \Prize\ (pr[imac]z), n. [F. prise a seizing, hold, grasp,
   fr. pris, p. p. of prendre to take, L. prendere, prehendere;
   in some senses, as 2
   (b), either from, or influenced by, F. prix price. See
       Prison, Prehensile, and cf. Pry, and also Price.]
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   1. That which is taken from another; something captured; a
      thing seized by force, stratagem, or superior power.
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            I will depart my pris, or my prey, by deliberation.
                                                  --Chaucer.
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            His own prize,
            Whom formerly he had in battle won.   --Spenser.
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   2. Hence, specifically;
      (a) (Law) Anything captured by a belligerent using the
          rights of war; esp., property captured at sea in
          virtue of the rights of war, as a vessel. --Kent.
          --Brande & C.
      (b) An honor or reward striven for in a competitive
          contest; anything offered to be competed for, or as an
          inducement to, or reward of, effort.
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                I'll never wrestle for prize more. --Shak.
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                I fought and conquered, yet have lost the prize.
                                                  --Dryden.
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      (c) That which may be won by chance, as in a lottery.
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   3. Anything worth striving for; a valuable possession held or
      in prospect.
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            I press toward the mark for the prize of the high
            calling of God in Christ Jesus.       --Phil. iii.
                                                  14.
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   4. A contest for a reward; competition. [Obs.] --Shak.
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   5. A lever; a pry; also, the hold of a lever. [Written also
      prise.]
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   Prize court, a court having jurisdiction of all captures
      made in war on the high seas. --Bouvier.

   Prize fight, an exhibition contest, esp. one of pugilists,
      for a stake or wager.

   Prize fighter, one who fights publicly for a reward; --
      applied esp. to a professional boxer or pugilist. --Pope.

   Prize fighting, fighting, especially boxing, in public for
      a reward or wager.

   Prize master, an officer put in charge or command of a
      captured vessel.

   Prize medal, a medal given as a prize.

   Prize money, a dividend from the proceeds of a captured
      vessel, etc., paid to the captors.

   Prize ring, the ring or inclosure for a prize fight; the
      system and practice of prize fighting.

   To make prize of, to capture. --Hawthorne.
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WordNet (r) 3.0 (2006):

prize money
    n 1: any money given as a prize