down
n. uncountable A1 Beginner Oxford US //ˈdaʊn// UK //dˈaʊn// down
n. the very soft, fine feathers on a young bird. People use these feathers, or similar ones from adult birds like geese, to fill jackets and pillows to make them warm.
n. the soft, fine feathers of a young bird, or the under-plumage of an adult bird such as a duck or goose, valued as a lightweight thermal insulator.
My winter jacket is filled with down.
She bought a new duvet filled with goose down to stay warm during the cold winter nights.
The nest was lined with moss and the softest down, a delicate cradle meticulously prepared for the fragile eggs that would soon occupy it.
From Irish dún (“fortress, stronghold”).
Usage
Often used attributively in compound nouns, such as 'down jacket' or 'down pillow'.