Definition from Wiktionary, the free dictionary
menaion (plural menaia)
- The annual fixed liturgical cycle of services used in the Eastern Orthodox and Greek-Catholic Churches, containing a list of the services and large collection of liturgical texts for an entire month. Twelve volumes are usually offered for the year, as a set known as the menaia.
- General Menaion - a book which contains services for each type of celebration (apostles, martyrs, etc.) with blank spaces for the name of the saint being celebrated.
- Festal Menaion - an anthology which contains the texts for those Great Feasts of the Lord or the Theotokos which fall on the fixed cycle, and optionally feasts of the major saints.