How do I know the missing word isn’t [up]coming, as in “Friday (coming [up] (this)) week”? As opposed to next week, which would be “Friday (next) week” in this syntax.

For that matter, the missing word could be this, as in “Friday (this) week” versus “Friday (that (as in the next one after the one contrasted with via the word this) week”. I have no way to disambiguate this, so I ask something like “Friday after tomorrow” or “Friday the 13th” or something. It’s hard being me at times, I’ll admit.

In Norwegian that means 9:30. It is indeed very common, that’s how we say every x:30. It’s «halfway to ten» or something.

I hear this in the US when people say "a couple things" instead of "a couple of things". The word "of" is missing!

In Dutch the literal translation is "half tien" which means 9:30 in Dutch. This can be quite confusing ;)

In Germany it‘s even more confusing. In the West people say „Viertel nach Neun“ and “Viertel vor Zehn” which is pretty much „quarter past nine“ and “quarter to ten”, while in Eastern Germany people say “Viertel Zehn” and “Dreiviertel Zehn” which rather means “quarter of ten” and “three quarters of ten”. Even though they are meaning exactly the same times.

My English-speaking father with German heritage said both “quarter to ten” for 9:45 and “quarter of ten” for 10:15. He’s the only person I’ve heard say “quarter of ten”. Now I know that could be from his German heritage even though he never learned German.