from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun The period beginning with the birth of Jesus.
from the GNU version of the Collaborative International Dictionary of English.
- The era in use in all Christian countries, which was intended to commence with the birth of Christ. The era as now established was first used by Dionysius Exiguus (died about 540), who placed the birth of Christ on the 25th of December in the year of Rome 754, which year he counted as 1 a. d. This date for Christ's birth is now generally thought to be about four years too late.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun the time period beginning with the supposed year of Christ's birth
Sorry, no etymologies found.
It is dignified and made precious by traditions which go back much further than the Christian era; and it has this tremendous advantage -- it exists!
His history commences with the Christian era, and is carried down to the year 1349.