The Collaborative International Dictionary of English v.0.48:

Snook \Snook\, n. [D. snoek.] (Zool.)
   (a) A large perchlike marine food fish (Centropomus
       undecimalis) found both on the Atlantic and Pacific
       coasts of tropical America; -- called also ravallia,
       and robalo.
   (b) The cobia.
   (c) The garfish.
       [1913 Webster]