Definition of futons:
(n) :
A thin mattress of tufted cotton or similar material, placed on a floor or on a raised, foldable frame as a bed.
(n) :
A specific kind of sofa-bed, with a fixed cushion that forms a mattress when folded down and a sofa when folded up.
(n) :
A round cushion used for Zen meditation, traditionally made of woven bulrush leaves.
(n) :
Abbreviation of full text on the Net: the presence of the complete text of an academic paper on the Internet, seen as a potential biasing factor in which papers get cited most often.