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.
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