wakefulness maintained for any reason during the normal hours for sleeping.
a watch or a period of watchful attention maintained at night or at other times: The nurse kept her vigil at the bedside of the dying man.
a period of wakefulness from inability to sleep.
Ecclesiastical. a devotional watching, or keeping awake, during the customary hours of sleep. Sometimes, vigils. a nocturnal devotional exercise or service, especially on the eve before a church festival. the eve, or day and night, before a church festival, especially an eve that is a fast.
a purposeful watch maintained, esp at night, to guard, observe, pray, etc