Homonym: Down (Downward)
Down refers to the soft, fluffy feathers found beneath the tougher exterior feathers of birds, primarily waterfowl like ducks and geese. These feathers provide excellent insulation, making them highly sought after for use in bedding and clothing, such as jackets and sleeping bags.
Due to its lightweight and compressible nature, down is favored for its ability to trap heat while remaining breathable. However, ethical concerns regarding the sourcing of down have led to the rise of alternatives like synthetic insulation, which aims to mimic the properties of down without the associated animal welfare issues.