facilities

A regular -y to -ies plural that carries every meaning of the singular. Most often it counts physical provisions, such as an airport's lounges or a clinic's equipment, or whole buildings designed for a purpose. In banking it can count credit facilities. In US and Canadian usage the singular's toilet meaning also lives in the plural, the use covered by the polite word for a toilet.

A euphemism that works by vagueness: "the facilities" points at the toilet without naming it, so it is safe in restaurants, offices and polite conversation. It is always plural and almost always takes "the". The understatement also invites humor. Sue Grafton's narrator in Q Is for Quarry (2002) "christened the facilities" before heading out, a wry use the plain word toilet could not manage.

A plural that names a whole set of provisions at once rather than counting separate ones. A hotel's gym, pool and meeting rooms together are its facilities, and the word takes a plural verb: the facilities were poorly maintained. The singular facility can stand in for it only in certain contexts, so when you mean the amenities of a place as a group, the plural is the natural choice.