Webster's Revised Unabridged Dictionary · 1913

Compline

Compline , noun

[From Old English complie, Old French complie, French complies, pl., from Late Latin completa (prop. fem. of Latin completus) the religious exercise which completes and closes the service of the day. See Complete.]

(Ecclesiastical) The last division of the Roman Catholic breviary; the seventh and last of the canonical hours of the Western church; the last prayer of the day, to be said after sunset.
The custom of godly man been to shut up the evening with a compline of prayer at nine of the night. — Hammond

Also: Complin