Any one of several species of large Old World ducks of the genus Tadorna and allied genera, especially the European and Asiatic species. (Tadorna cornuta syn. Tadorna tadorna), which somewhat resembles a goose in form and habit, but breeds in burrows.

large crested fish-eating diving duck having a slender hooked bill with serrated edges

Old World gooselike duck slightly larger than a mallard with variegated mostly black-and-white plumage and a red bill

Any one of the American mergansers.