canonical hours

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun plural The times of day, historically including matins, lauds, prime, terce, sext, nones, vespers, and compline, at which canon law prescribes certain prayers to be said.
• noun plural The prayers said at these times.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun plural The times of day at which canon law prescribes certain prayers to be said; matins with lauds, prime, tierce, sext, nones, vespers, and complin
• noun The prayers said at these times