Todas essas expressões são usadas em inglês para ir ao banheiro, toalete, BWC etc hehehe
Restroom: "Can I use the restroom?"
Where can I wash my hands?
public conveniences: "Are there any public conveniences nearby?"
ladies / gents: "The ladies and gents are down the corridor on your right."
Can I use your bathroom?
the bog: "He's in the bog."
the smallest room of the house: "I'd like to pay a visit to the smallest room of the house."
powder my nose: "Where can I powder my nose?"
see a man about a dog: "He's gone to see a man about a dog."