The Collaborative International Dictionary of English v.0.48:

Cabezon \Cab`e*zon"\ (k[a^]b`[asl]*z[o^]n" or
   k[aum]*b[asl]*th[-o]n"), n. [Sp., properly, big head. Cf.
   Cavesson.] (Zool.)
   A California fish (Hemilepidotus spinosus), allied to the
   sculpin.
   [1913 Webster]