irmologionEtymologyFrom Ancient Greek εἱρμολόγιον (heirmológion).nounA liturgical book containing irmoi for the various canons chanted during the morning service.“Although an Irmologion, as its name suggests, is essentially a collection of irmosy or the nine hymns sung during Matins, the earlier Belorussian Irmologia contain in addition all manner of chants from the Holy Liturgy, Vespers and Matins, Festival and Holy Week services, […]”