The Collaborative International Dictionary
Menaion \Me*na"ion\, n.; pl. Menaia (-y[*a]). [NL., from Gr. ?
A work of twelve volumes, each containing the offices in the
Greek Church for a month; also, each volume of the same.
n. 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''.
The Menaion (; Slavonic: Минеѧ, Minéya, "of the month") is the liturgical book used by the Eastern Orthodox Church containing the propers for fixed dates of the calendar year, i.e. entities not dependent of the date of Easter.
The Menaion is the largest volume of the propers for the Byzantine Rite and is used at nearly all the daily services.