vigil Definition

vigil
noun

1. A period of staying awake, usually to guard or watch over a person or thing.

Thesaurus: lookout, sentry duty, wakefulness, watchfulness, watch.
2. A stationary, peaceful demonstration for a specific cause.
3. The day before a major religious festival, traditionally spent in prayer.
4. A night-time religious service or session of prayer.

Etymology: 13c: from Latin vigila, from vigil, meaning ‘awake' or ‘watchful'.