a small, North American duck (Oxyura jamaicensis), the breeding male of which has a brownish-red neck and upper body, black crown, white cheeks, and blue bill
See ruddy duck in American Heritage Dictionary 4
noun
A North American duck (Oxyura jamaicensis) having stiff pointed tail feathers and, in the male, brownish-red upper plumage and a black-and-white head. Also called sprigtail.