Regulated profession. In this context, a profession would essentially be a catch-all for paid work. And a Profession would be paid work for a specific regulated body of "Professionals" with a specific designation or exclusive right to practive. Think doctor, lawyer, accountant.
Or in the UK - Engineer. Not a protected Profession in the US, but is here.
I believe there are PE's in the US - similar to UK CEng.
Depends what kind of engineer you're talking about. You need a license to practice Engineering[0] in the US. It's just that software developers aren't considered Engineers.