Source : Webster's Revised Unabridged Dictionary (1913)

Cobia \Co"bi*a\, n. (Zo["o]l.)
   An oceanic fish of large size ({Elacate canada}); the
   crabeater; -- called also {bonito}, {cubbyyew}, {coalfish},
   and {sergeant fish}.

Source : WordNet®

sergeant fish
     n : large dark-striped tropical food and game fish related to
         remoras; found worldwide in coastal to open waters [syn:
         {cobia}, {Rachycentron canadum}]