社会人 https://en.wiktionary.org/wiki/%E7%A4%BE%E4%BC%9A%E4%BA%BA is a Japanese coined Kanji term, meaning "**working adult**" (not children who don't work, not students who work part time, not retired people)

The Chinese counterpart of "社会人" is "在職人仕" 

Any adult who is making a living by working or trading is considered a "在職人仕" or "在職者"

If you see Chinese article  using the term 社会人, it is most likely reverse imported from Japanese language (Japanese coined the term with the Kanji they learned from Chinese and now the Chinese is accepting this term in the Chinese language)

Notice: *Chinese consider 社会 is made up by everyone in it, therefore "社会上的人" (people in society) would include students and retired people*