noun
down quilt; feather futon
A thick, warm futon filled with down or feathers, used as a top cover in traditional Japanese bedding.
冬は羽布団がないと寒くて眠れない。
In winter, I can't sleep without a down futon because it's too cold.
軽くて暖かい羽布団を買い替えた。
I replaced my light and warm down futon.
Compound of 羽 (はね, 'feather') and 布団 (ふとん, 'futon'). The kanji 羽根 (feather) is sometimes used explicitly, and 蒲団 is an older spelling of 布団.