What does "jackman" mean?

Jackman: A cream cheese. [Obs.] Sir T. Elyot. JACK-O'-LANTERN Jack"-o'-lan`tern, n. See Jack-with-a-lantern, under 2d Jack. JACKPOT Jackpot

Additional senses

  1. 2.(a) See "jack pot" under jack; (b) any larger-than-usual gambling prize formed by the accumulation of unwon bets[=MW10 1(a)(2) and 1(c)]; (c) the highest gambling prize awarded in a gambling game in which smaller prizes are also awarded, especially such a prize on a slot machine.
  2. 3.(a) An unusually large success in an enterprise, either unexpected or unpredictable, esp. one providing a great financial benefit. hit the jackpotto receive an unexpectedly large (or the largest possible) benefit from an enterprise.

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