Eiderdown, or eider down, comes from the Common Eider Duck, a large migratory sea duck. The common eider duck ranges along the northern coasts of eastern Siberia, Europe and North America. Approximately 85-90% of the worlds eiderdown comes from Iceland, 10-15% comes from Canada.

Where did the term eiderdown come from?

eiderdown (n.)

"soft feathers of the eider-duck" (such as it uses to line its nest), 1774; see eider + down (n. 1). Ultimately from Icelandic æðardun, via a Scandinavian source (compare Danish ederdunn) or German Eiderdon.

What is the difference between an eiderdown and a duvet?

As nouns the difference between eiderdown and duvet

is that eiderdown is (uncountable) the down of the eider duck, used for stuffing pillows and quilts while duvet is (british|new zealand) a thick, padded quilt used instead of blankets.