nocturn

noun Roman Catholic Church.

1. the office of matins, consisting of nine psalms and either three or nine lessons.

noun

1. 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).