The Collaborative International Dictionary of English v.0.48:

Gadoid \Ga"doid\ (?; 277), a. [NL. gadus cod + -oid: cf. F.
   gado["i]de gadoid, Gr. ? a sort of fish, F. gade.] (Zool.)
   Of or pertaining to the family of fishes (Gadid[ae]) which
   includes the cod, haddock, and hake. -- n. One of the
   Gadid[ae]. [Written also gadid.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

gadoid
    n 1: a soft-finned fish of the family Gadidae [syn: gadoid,
         gadoid fish]