AD

Latin, anno domini, ‘in the year of the Lord’, commonly used by Christians to indicate dates, from the supposed date of the birth of Jesus in the year 1. The years before his birth are designated ‘BC’, Before Christ. However, Jesus was born, according to Matt. and Luke, while Herod was reigning, and he died in 4 BCE. Jesus' birth is therefore reckoned to have taken place in 4 BCE or just before, and the incorrect date is due to imprecise calculations by a Scythian monk, Dionysius, in the 6th cent. CE. See chronology of the New Testament.