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Holman Bible Dictionary [1]

 Luke 1:26-38 Judges 13:2-5 Matthew 1:20-25 Luke 1:11-20

The Feast of the Annuniciation is celebrated on March 25 (Lady Day) by Roman Catholics, Anglicans, and Orthodox Christians. The first references to the feast, besides the Gelasian and Gregorian sacramentaries, are in acts of the Council of Toledo (656) and of the Trullan Council (692).

Webster's Dictionary [2]

(1): (n.) The festival celebrated (March 25th) by the Church of England, of Rome, etc., in memory of the angel's announcement, on that day; Lady Day.

(2): (n.) The announcement of the incarnation, made by the angel Gabriel to the Virgin Mary.

(3): (n.) The act of announcing; announcement; proclamation; as, the annunciation of peace.

Charles Buck Theological Dictionary [3]

The tidings brought by the angel Gabriel to the virgin Mary of the incarnation of Christ. It is also used to denote a festival kept by the church on the 25th of March, in commemoration of these tidings.

Hawker's Poor Man's Concordance And Dictionary [4]

See Mary