n.duck of the northern hemisphere much valued for the fine soft down of the females
同义词：eider
英汉双解大词典
eider(alsoeiderduck)
1.
N（名词）
any of several sea ducks of the genus Somateria, esp S. mollissima, and related genera, which occur in the N hemisphere. The male has black and white plumage, and the female is the source of eiderdown 绒鸭