Pillow filling is a material used to stuff pillows and provide comfort and support. The crossword solutions for the term pillow filling include DOWN (4 letters), EIDERDOWN (9 letters), EIDER (5 letters) and goosedown (9 letters). DOWN is a soft, fluffy material made from the undercoating of birds such as ducks and geese. EIDERDOWN is a type of DOWN that comes from the EIDER duck, which is native to the Arctic regions. Goosedown is a type of DOWN that comes from geese. All of these materials are lightweight and provide excellent insulation and cushioning.