Down or soft feathers of the eiderduck, such as the bird plucks from its breast to line the nest or cover the eggs.(noun)
The Century Dictionary (Public Domain)
Use "eider-down" in a sentence
"Under the luxurious hanging draperies, the pillow, crushed into the depths of an eider-down quilt, its lace border standing out in contrast against the background of blue silk, bore a vague impress that kindled the imagination."
"The same evening in a little room, beside a bed covered with a striped eider-down, Onisim was sitting at a clumsy little table, facing Vassilissa."
"Five-and-twenty years of tent, open sky, jungle, and who knows what, for him — but eider-down, and fireside, and fat of land for them!"