Polychronion
The Polychronion (Greek: Πολυχρόνιον, "many years"; Georgian: მრავალჟამიერი, mravaljamieri; Church Slavonic: многая лѣта, romanized: mnogaya leta) is a solemn encomium chanted in the liturgy of the Eastern Orthodox and Byzantine Catholic churches. In the Roman rite, it is the equivalent of the liturgical acclamation Ad multos annos.