I know this is a repetitive question, but still can't get if the word is used in English when talking about alleys and narrow passages!
Unfortunately, I've seen some street signs which read 'Impass 9', or 'Impass Rose', etc. The '9' would simply mean it's the 9th alley in that street, and 'Rose' is the name of the alley.
Is that really correct to use the word 'Impass' in English meaning it's a dead-end alley?!
We use cul-de-sac, dead end, no outlet or no through road.
I regret to say in a town in Iran! I wondered if it was put in French or something. At least I'm sure it wasn't in English!