Any of numerous fishes constituting the teleostean order Pleuronectiformes, having flat bodies with both eyes on one side, swimming with the eyeless side down, and including sole, plaice, turbot, etc.; a flatfish.
Mid 19th century. From scientific Latin Pleuronectes, genus name (valid publication LinnaeusSystema Naturae I. 268) from pleuro- + Hellenistic Greek νήκτης swimmer.