Any of the species of the genera Polysticta or Somateria, in the seaduck subfamily Merginae, which line their nests with fine down (taken from their own bodies).

plural of eider

A river in Germany, the boundary between Schleswig and Holstein.

plural of common eider

A sea duck in the eider family; Somateria mollissima.

A large sea duck that breeds along Arctic coasts, Somateria spectabilis.

plural of king eider

(uncountable) The down of the eider duck, used for stuffing pillows and quilts. / (countable) A quilt stuffed with this down.

plural of eiderduck

An eider.