noun
loo
LOO/luː/
A toilet or a room containing one.
The modern loo stands beside a wall-mounted toilet-paper holder.

Etymology
The origin of this bathroom word is uncertain. Suggested explanations include a French expression meaning “place of ease” and a pun on Waterloo prompted by “water closet.”
In context
buildings have the loo the restroom the washroom in one particular place on each floor of each building