A canonarch is a lead cantor or reader in Orthodox Christian churches of the Byzantine tradition. The office was used especially during the times when antiphonal singing was common. The office has generally fallen out of use in the modern age. The canonarch ensures that readers chant from the correct texts and use the proper tones during church services. The canonarch preserves the canonical order in the liturgical services through proper use of the Typicon.
The canonarch is of higher rank than the reader, but lower than a deacon and is at the same level as a subdeacon. In some Old Rite usages a subdeacon doubles as the canonarch. He is tonsured. In more recent times many of the duties of the canonarch have been assumed by deacons.
The canonarch was usually a member of one of the antiphonal choirs. Before he begins his duties he enters the altar to receive a blessing and to vest himself in the sticharion. Then, he leaves the altar and takes his place in the middle of the church. He stands in the church under the rotunda or chandelier, or before the Royal Doors. The canonarch also reads the verses of the Prokeimenon, the Alleluia, and related texts.