noun, adverb
post-era; after the epoch
Used in historical or chronological contexts to refer to the period after a specific era or epoch, often in contrast to 紀元前 (pre-era). Can function as a noun or adverbially.
この遺跡は紀元後のものだ。
These ruins are from the post-era period.
紀元後の歴史を研究している。
I am researching post-era history.