Vigil

Abstinence from sleep, whether at a time when sleep is customary or not; the act of keeping awake, or the state of being awake, or the state of being awake; sleeplessness; wakefulness; watch.

Hence, devotional watching; waking for prayer, or other religious exercises.

Originally, the watch kept on the night before a feast.

Later, the day and the night preceding a feast.

A religious service performed in the evening preceding a feast.

a period of sleeplessness