jackpot \jackpot\, n.
   1. same as jack pot. see under jack.
      pjc

   2. any larger-than-usual gambling prize formed by the
      accumulation of unwon bets.
      pjc

   3. the highest gambling prize awarded in a gambling game in
      which smaller prizes are also awarded, especially such a
      prize on a slot machine.
      pjc

   4. an unusually large success in an enterprise, either
      unexpected or unpredictable, esp. one providing a great
      financial benefit.
      pjc

   hit the jackpot to receive an unexpectedly large or the
      largest possible benefit from an enterprise; as, after
      prospecting for years, he finally hit the jackpot when he
      discovered a silver lode.
      pjc
see also:
jack pot jack hit the jackpot 

hit the jackpot
     v : succeed by luck; "i lucked out and found the last parking
         spot in the lot" syn: luck out
see also:
luck out