- any of several thick-bodied, sluggish fishes of the family Cyclopteridae, found in northern seas, having the pelvic fins modified and united into a sucking disk, especially Cyclopterus lumpus, of the North Atlantic.
- a North Atlantic scorpaenoid fish, Cyclopterus lumpus, having a globular body covered with tubercles, pelvic fins fused into a sucker, and an edible roe: family Cyclopteridae
- any other fish of the family Cyclopteridae
