Formal:
* Banheiro: This is the most common and neutral term for restroom.
* Casa de banho: This is a more formal and literary term, often used in written language.
Informal:
* Toalete: This is a more casual term for restroom.
* W.C.: This is an abbreviation for "water closet" and is often used in informal settings.
* Sanitário: This is a less common term for restroom.
Other:
* Lavabo: This term refers specifically to a sink, but can also be used to refer to a restroom, especially in older buildings.
* Serviço de higiene: This is a literal translation of "hygiene service" and is sometimes used to refer to a restroom.
It's important to note that the use of these terms can vary depending on the region. For example, "toalete" is more common in Brazil, while "casa de banho" is more common in Portugal.
If you're unsure which term to use, it's always safe to ask "Onde é o banheiro?" or "Onde fica o banheiro?" in Portuguese.