The Collaborative International Dictionary of English v.0.48:

Jewfish \Jew"fish`\, n. (Zool.)
   1. A very large serranoid fish (Promicrops itaiara) of
      Florida and the Gulf of Mexico. It often reaches the
      weight of five hundred pounds. Its color is olivaceous or
      yellowish, with numerous brown spots. Called also guasa,
      and warsaw.
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   2. A similar gigantic fish (Stereolepis gigas) of Southern
      California, valued as a food fish.
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   3. The black grouper of Florida and Texas.
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   4. A large herringlike fish; the tarpum.
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