- This abbreviation (from the Latin, anno Domini, meaning "in the year of the Lord") originated with Dionysius Exiguus (died ca. 544), who proposed beginning the enumeration of years with the birth of Jesus Christ; due to a miscalculation, the exact year of Christ's birth was probably four to six years earlier (6-4 BC).
Glossary of theological terms. John T. Ford. 2014.