The Collaborative International Dictionary of English v.0.48:

Lumpfish \Lump"fish`\, n. [From Lump, on account of its
   bulkiness: cf. G. & D. lump, F. lompe.] (Zool.)
   A large, thick, clumsy, marine fish (Cyclopterus lumpus) of
   Europe and America. The color is usually translucent sea
   green, sometimes purplish. It has a dorsal row of spiny
   tubercles, and three rows on each side, but has no scales.
   The ventral fins unite and form a ventral sucker for adhesion
   to stones and seaweeds. Called also lumpsucker,
   cock-paddle, sea owl.
   [1913 Webster]

WordNet (r) 3.0 (2006):

lumpfish
    n 1: clumsy soft thick-bodied northern Atlantic fish with pelvic
         fins fused into a sucker; edible roe used for caviar [syn:
         lumpfish, Cyclopterus lumpus]