When you want to try a piece of clothing on, in a clothing shop, you go to this small stall to try it on.
Would you please tell me what you call this room?
We pronounce it /prov/ in here.
In BrE, "fitting room" or "changing room", but usually the former. The entire area is called the fitting room but usually it contains several individual sections with their own door so that people can try on their clothes in privacy. Each one is a "cubicle".
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