diptych

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A work consisting of two painted or carved panels that are hinged together.
• noun An ancient writing tablet having two leaves hinged together.
• noun A list of names, originally contained on such a tablet, of living and dead Christians for whom special prayers are made during the liturgy in many eastern and western churches.

from The Century Dictionary.

• noun A hinged two-leaved tablet of wood, ivory, or metal, with waxed inner surfaces, used by the Greeks and Romans for writing with the style.
• noun In the early church: The tablets on which were written the names of those who were to be especially commemorated at the celebration of the eucharist.
• noun The list of names so recorded.
• noun The intercessions in the course of which these names were introduced.
• noun In art, a pair of pictures or carvings on two panels hinged together.

from the GNU version of the Collaborative International Dictionary of English.

• noun Anything consisting of two leaves.
• noun (Roman Antiq.) A writing tablet consisting of two leaves of rigid material connected by hinges and shutting together so as to protect the writing within.
• noun A picture or series of pictures painted on two tablets connected by hinges. See triptych.
• noun A double catalogue, containing in one part the names of living, and in the other of deceased, ecclesiastics and benefactors of the church; a catalogue of saints.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A writing tablet consisting of two leaves of rigid material connected by hinges and shutting together so as to protect the writing within.
• noun art A picture or series of pictures painted on two tablets, usually connected by hinges.
• noun A double catalogue, containing in one part the names of living, and in the other of deceased, ecclesiastics and benefactors of the church.
• noun A catalogue of saints.
• noun Artistically-wrought tablets distributed by consuls, etc. of the later Roman Empire to commemorate their tenure of office; hence transferred to a list of magistrates
• noun a. a literary work consisting of two contrasting parts (as a narrative telling the same story from two opposing points of view) "a diptych, a pastoral in which the author narrates the birth of Christ ... first as it has impressed the rich countryman Asveer, then as it has been seen by the skeptic Nicodemus" -- François Closset b. any work made up of two matching parts treating complementary or contrasting pictorial phases of one general topic "the first volume of a diptych Vegetation and Flora of the Sonoran Desert" -- F.E. Egler

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a painting or carving (especially an altarpiece) on two panels (usually hinged like a book)