1. a large sea duck of northern regions, the female of which has valuable soft down feathers

Examples

• The eider is known for its exceptionally warm down feathers.
• Eiders nest in colonies along rocky coastlines.
• The female eider plucks her own down to line the nest.
• Eider down is highly prized for making luxury bedding.
• We spotted a flock of eiders diving for shellfish.
• The male eider has distinctive black and white plumage.
• Eiders are well-adapted to cold Arctic waters.