Since I wrote the post English versus American I learned a lot about this very commun place which everybody in the world, even Kings and Queens, Princesses and Princes use .... a toilet.
According to Wikipedia , a toilet is a sanitation fixture used primarily for the disposal of human excrement, often found in a small room referred to as a toilet/bathroom/lavatory.
The WC refers to the initial letters of Water Closet, which, despite being an English language abbreviation, is not in common use in English-speaking countries - but is widely used internationally.
It depends where you are in the world. You have to know what to ask for :
"The washroom, restroom, bathroom, lavatory, toilet room, toot or loo, comfort station, necessary room, John, ladies' room, men's room, latrine, lavatory, powder room, privy ...
Honnestly why would I ask for a comfort station, when it is not comfortable at all to sit there in silence or a restroom unless the toilet is incorporated in a bed, or for a John, when I don't have one, and a powder room, when I don't use powder anymore or at least not there, where it is used for babies.
Follow these signs ?
But if there are none, for what should I ask ?? I want to be polite and not make a mistake when I only have to go for a little wee-wee ?