Common Eider

Somateria mollissima

Eiderdown, the soft filling for luxury quilts and pillows, is named for this duck, which lines its nest with its own down. Its scientific name is about the same thing: 'woolly body, very soft.'

Somateria joins the Greek sōma, 'body,' and erion, 'wool'; mollissima is Latin for 'very soft.' 'Eider' comes from the Icelandic æður. In northern England it's still called St. Cuthbert's duck, or Cuddy's duck, after the region's patron saint.