- Anglo-Saxon: aefen
- Latin: vigilia, watch
Day of preparation before a great feast. In the early ages the evening and night before a feast were spent in prayer, fasting, Scripture-reading, and preaching. Since the 11th century the observance, beginning in the morning, consists of special Mass and Office and fasting. In the Roman calendar, besides Holy Saturday, there are 17 vigils: the eves of Christmas, Epiphany, Ascension, Pentecost, Immaculate Conception, Assumption, eight feasts of the Apostles, and feasts of Saint John the Baptist, Saint Lawrence, and All Saints. Some dioceses and religious orders have special vigils. Those of Christmas, the Epiphany, and Pentecost are major vigils and have a proper office, the vigil of Christmas being a double feast; the others are minor vigils and have a ferial office. If a vigil falls on Sunday it is kept on the preceding Saturday, if it falls on a double or semi-double feast it is limited to a commemoration at Lauds and in the Mass. In the United States, England, Scotland, and Ireland the vigils of Christmas, Pentecost, the Assumption, and All Saints are fast days.