Source : Webster's Revised Unabridged Dictionary (1913)

Monkfish \Monk"fish\, n. (Zo["o]l.)
   (a) The angel fish ({Squatina}).
   (b) The angler ({Lophius}).

Source : WordNet®

monkfish
     n 1: flesh of a large-headed anglerfish of the Atlantic waters of
          North America
     2: fishes having large mouths with a wormlike filament attached
        for luring prey [syn: {goosefish}, {angler}, {anglerfish},
         {angler fish}, {lotte}, {allmouth}, {Lophius Americanus}]
     3: sharks with broad flat bodies and winglike pectoral fins but
        that swim the way sharks do [syn: {angel shark}, {angelfish},
         {Squatina squatina}]
     [also: {monkfishes} (pl)]