The Pentecostarion (Greek: Πεντηκοστάριον, Pentekostárion; Slavonic: Цвѣтнаѧ Трїωдь, Tsvyetnaya Triod' , literally "Flowery Triodon"; ) is the liturgical book used by the Eastern Orthodox and Eastern Catholic Churches which follow the Byzantine Rite during the Paschal Season which extends from Pascha (Easter) to the Sunday following All Saints Sunday (i.e., the Second Sunday After Pentecost).