Cottus is a genus of the mainly freshwater ray-finned fishes belonging to the family Cottidae, the typical sculpins. They are often referred to as the "freshwater sculpins", as they are the principal genus of sculpins to be found in fresh water. They are native to the Palearctic and Nearctic.

The Cottidae are a family of fish in the superfamily Cottoidea, the sculpins. It is the largest sculpin family, with about 275 species in 70 genera. They are referred to simply as cottids to avoid confusion with sculpins of other families.