On-board toilet

image:Airbus-Bordtoilette.jpg|thumb|On-board toilet of an aircraft
On-board toilets are enclosures equipped with a toilet for the use of human excretion, typically mounted within a vehicle.
The small rooms also often are equipped with at least a sink, liquid soap, and paper towels for hand washing. Except in luxury versions, toilets of this kind are usually small.
The excreta are stored in a holding tank or, on some ships, piped overboard. They are found in large aircraft, ships including crewed spacecraft, some road vehicles and many passenger train cars.