Question

what do you understand by the term 'Anno Dommini'

Answer 1

Today the international standard is to designate years based on a traditional reckoning of the year Jesus was born — the “A.D.” and "B.C." system. "A.D." stands for anno domini, Latin for “in the year of the lord,” and refers specifically to the birth of Jesus Christ. "B.C." stands for "before Christ."
Anno dommini