Definitions
1.nounA door, window, shutter, or divider consisting of two equal panels hinged together so that it opens by folding the panels against each other.
2.nounA sheet of paper or cardboard folded in half along a crease down the center.
3.nounA wallet, billfold, or carrying case with a single fold, so that it opens like a book.
4.nounA crease or turn that causes something to double back on itself.
5.adjectiveTwofold, double.
6.adjectiveOf two kinds.