eider

noun

1. duck of the northern hemisphere much valued for the fine soft down of the females

   noun.animal

   Synonyms eider duck

   Source: WordNet 3.0

2. Any species of sea duck of the genus <i>Somateria</i>, esp. <i>Somateria mollissima</i>, which breeds in the northern parts of Europe and America, and lines its nest with fine down (taken from its own body) which is an article of commerce; -- called also <i>eider duck</i>. The American eider (<i>S. Dresseri</i>), the king eider (<i>S. spectabilis</i>), and the spectacled eider (<i>Arctonetta Fischeri</i>) are related species.

   noun

   Source: webster1913