What is the meaning of Futon?

A thin mattress of tufted cotton or similar material, placed on a floor or on a raised, foldable frame as a bed.

A round cushion used for Zen meditation, traditionally made of woven bulrush leaves.

A specific kind of sofa-bed, with a fixed cushion that forms a mattress when folded down and a sofa when folded up.

accusative singular of futo

futon

futon: a Japanese-style mattress or duvet; a thin mattress of tufted cotton or similar material, placed on a floor or on a raised, foldable frame as a bed.

Rōmaji transcription of ふとん

Source: wiktionary.org