noun Roman Catholic Church.
- the office of matins, consisting of nine psalms and either three or nine lessons.
noun
- RC Church any of the main sections of the office of matins
n.a division of the office of matins, early 13c., from Old French nocturne “evening service; curfew,” from Medieval Latin nocturna, “group of Psalms used in the nocturns,” from Latin nocturnus (see nocturnal).