Synaxarion or Synexarion (plurals Synaxaria, Synexaria; , from συνάγειν, synagein, "to bring together"; cf. etymology of synaxis and synagogue; Latin: Synaxarium, Synexarium; ; ) is the name given in the Eastern Orthodox, Oriental Orthodox and Eastern Catholic Churches to a compilation of hagiographies corresponding roughly to the martyrology of the Roman Church. There are two kinds of synaxaria: Simple synaxaria: lists of the saints arranged in the order of their anniversaries, e.g. the calendar of Morcelli Historical synaxaria: including biographical notices, e.g. the Menologion of Basil II and the synaxarium of Sirmond. The notices given in the historical synaxaria are summaries of those in the great menologies, or collections of lives of saints, for the twelve months of the year. As the lessons in the Byzantine Divine Office are mostly the lives of saints, the Synaxarion became the collection of short lives of saints and martyrs, but also of accounts of events, of famous visions seen by saints and even useful narratives whose memory is kept. Definitions The exact meaning of the name has changed at various times. Its first use was for the index to the Biblical and other lessons to be read in church. In this sense it corresponds to the Latin Capitulare and Comes. Then the Synaxarion was filled up with the whole text of the pericopes to be read. As far as the Holy Liturgy was concerned this meant that it was essentially transformed into the "Gospel" and "Apostle" books. Synaxarion remained the title for the index to the other lessons. Without changing its name it was filled up with complete texts of these lessons. The mere index of such lessons is generally called menologion heortastikon, a book now hardly needed or used, since the Typikon supplies the same, as well as other, information. Certain calendars extant in the Middle Ages were also called Synaxaria. Krumbacher describes those composed by Christopher of Mytilene and Theodore Prodromus (twelfth century). Examples The oldest historical synaxaria apparently go back to the tenth century. There are a great number of medieval synaxaria extant in manuscript. They are important for Byzantine heortology and church history. The short lives that form the lessons were composed or collected by various writers. Of these Symeon Metaphrastes is the most important. The accounts are of very varying historical value. Emperor Basil II (976-1025) ordered a revision of the synaxarion, which forms an important element of