“The 9[am] to 5[pm]” is a common term for one’s regular job, on the basis that normal people start work at 09:00 and finish at 17:00. I’ve worked a few jobs and closest I’ve ever gotten to this is 08:00 to 17:00, which I gather is standard.
Are there real jobs where people actually start at 9 and finish at 5?
I have not found one. If I come in at 9, leave at 18, or 18:30, if I come in at 8, same. So I come in at 9.
But in general here it’s a 9 hour day with an hour break for lunch, that makes the 8 hour workday.