Definition of: diptych

(dip′tik) noun
1. A double tablet; especially, two tablets of wood, metal, or ivory, hinged together and covered on the inside with wax, on which the ancient Greeks and Romans wrote with a stylus.
2. A cover for a book, resembling this.
3. A double picture or design on a pair of hinged tablets or panels. [<LL diptycha <Gk., pair of tablets; orig. neut. plural of diptychos folded <di- twice + ptyssein fold]