It sounds like a founder before they got a first seed round of investment, which usually leads to those first seed investors labelling themselves as “founders” too, so trying to differentiate with like “(co)-founded the business before we had external capital, e.g. did actual work instead of buying my way in.”

That being said though, generally in my experience the more someone talks about being a “founder” the less they actually did beyond secure funding and blabber on about “vision” and “product” while others did the real work.