Duple is a term used to describe something that is composed of two parts or elements. The term can be broken down into three different words: DUAL, TWOFOLD, and DOUBLE. DUAL is a four letter word meaning consisting of two parts or elements. TWOFOLD is a seven letter word meaning having two parts or elements. DOUBLE is a six letter word meaning twice as much or TWOFOLD. All three words refer to the same concept of having two parts or elements.