DIPTYCHS - (Gr. "folding boards"). 1) Lists of names for living and dead, written on cardboard for their commemoration in the liturgy.
2) An official roster of the names of the heads (primates) of Orthodox jurisdictions read during the liturgy by concelebrating bishops, or the head of an ecclesiastical jurisdiction.
3) A type of icon whereby two panels are joined together with a hinge, so that they may fold together for protection when traveling, and then be unfolded for veneration when one's destination has been reached. Such diptychs are also called "traveling icons". Most often, the images on the two panels will be Christ and the Theotokos.