Webster's Revised Unabridged Dictionary · 1913

Vespers

Vespers , noun, plural

[Old French vespres, French vêpres, Late Latin vesperae, from Latin vespera evening. See Vesper, n.]

(a)
(Roman Catholic Church) One of the little hours of the Breviary.
(b)
(Roman Catholic Church) The evening song or service.
Collocations (1)
Sicilian vespers , See under Sicilian, a.