any of certain marine fish of the family Cyclopteridae (order Scorpaeniformes), found in cold northern waters. Lumpsuckers are thickset, short-bodied, scaleless fish with skins that are either smooth or studded with bony tubercles. Like the snailfish, which are often included in the family, they are characterized by a strong sucking disk on the undersurface. The disk is formed from the pelvic fins and is used by the fish in holding firmly to the sea bottom.
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