eiders

/AY1 D ER0 Z/
noun
  1. 1

    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).

Source: https://en.wiktionary.org/wiki/eider, https://en.wiktionary.org/wiki/eiders