Source : Webster's Revised Unabridged Dictionary (1913)

Snook \Snook\ (sn[=oo]k), v. i. [Prov. E. snook to search out,
   to follow by the scent; cf. Sw. snoka to lurk, LG.
   sn["o]ggen, snuckern, sn["o]kern, to snuffle, to smell about,
   to search for.]
   To lurk; to lie in ambush. [Obs.]

Snook \Snook\, n. [D. snoek.] (Zo["o]l.)
   (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.

Source : WordNet®

snook
     n : large tropical American food and game fishes of coastal and
         brackish waters; resemble pike