a service forming part of the Divine Office of the Western Christian Church, traditionally said (or chanted) at the ninth hour of the day (3 p.m.)
the round-the-clock rhythm of praying the liturgical hours: matins, prime, terce, sext, none, vespers, compline
in the ancient Roman calendar, the ninth day before the ides by inclusive reckoning, i.e. the 7th day of March, May, July, October, the 5th of other months