eider eidently • eidetic · · · Info · Definitions · Synonyms · Characters · · eider · · Text Latin · · Script 5 · · Length Definitions · · · (noun) duck of the northern hemisphere much valued for the fine soft down of the females. Synonyms: eider duck. · · Noun Definition 1 Synonyms · · · eider duck · · Synonym 1 Characters · · d latin small letter d U+0064 e latin small letter e U+0065 i latin small letter i U+0069 r latin small letter r U+0072