Source : Webster's Revised Unabridged Dictionary (1913)

Jonah \Jo"nah\, n.
   The Hebrew prophet, who was cast overboard as one who
   endangered the ship; hence, any person whose presence is
   unpropitious.

   {Jonah crab} (Zo["o]l.), a large crab ({Cancer borealis}) of
      the eastern coast of the United States, sometimes found
      between tides, but usually in deep water.

Source : WordNet®

Cancer borealis
     n : large red deep-water crab of the eastern coast of North
         America [syn: {Jonah crab}]