Definition: Antoninianus was a Roman emperor who ruled in the early third century A.D. He is often associated with the fall of Constantinople to the Byzantine Empire. Definition: Antoinianus is the Latin term for "born of grace." The term is used to describe someone born into wealth, social status, or a particular position because they have been given certain advantages or gifts by God in their youth. This could include good health, education, or other divine qualities. For example: Antoninianus was born on the day of Pentecost, the same day as Jesus Christ. He grew up with the most lavish upbringing and opportunities that were available to him because he had been raised in a noble family.