"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.
Egyptian
Egyptology
eh
*ei-
eider
eiderdown
eidetic
eidolon
Eiffel Tower
eight
eighteen
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