Source : Webster's Revised Unabridged Dictionary (1913)

Sea catfish \Sea" cat`fish\ Sea cat \Sea" cat`\ (Zo["o]l.)
   (a) The wolf fish.
   (b) Any marine siluroid fish, as {[AE]lurichthys marinus},
       and {Arinus felis}, of the eastern coast of the United
       States. Many species are found on the coasts of Central
       and South America.

Source : WordNet®

sea catfish
     n : any of numerous marine fishes most of which are
         mouthbreeders; not used for food