n.
Pronunciation: ' ī -d ə r
Function: noun
Etymology: Dutch, German, or Swedish, from Icelandic æthur, from Old Norse æthr
Date: 1743
1 : any of several large northern sea ducks (genera Somateria and Polystica ) having fine soft down that is used by the female for lining the nest ― called also eider duck
2 : EIDERDOWN 1