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Urinal is a specialized toilet designed to be used only for urination, not defecation, and almost always by a standing male. Advantages over a full-function toilet include: it is smaller, uses much less water, and the regular version is for regular adults at a convenient higher height.

It often contains a urinal cake contained within a plastic mesh guard container or a plastic mesh guard without a urinal cake. The plastic mesh guard is designed to prevent solid objects such as cigarette butts or paper from being flushed and possibly causing a plumbing stoppage.

Urinal with strawberry flavored urinal cake.The term may also apply to a small building or other structure, in which such toilets are contained.

Flushing
Most urinals incorporate a flushing system to rinse urine from the bowl of the device to prevent foul odors. The flush can be triggered by one of several methods:

Manual handles
This type of flush might be regarded as standard in the United States. Each urinal is equipped with a button or short lever to activate the flush, with users expected to operate it as they leave. Such a directly-controlled system is the most efficient provided that patrons remember to use it. This is far from certain, however, often because of fear of touching the handle which is located too high to kick.[1] Urinals with foot-activated flushing systems are sometimes found in high-traffic areas; these systems have a button set into the floor or a pedal on the wall at ankle height. Some establishments, often bars, pubs or nightclubs, fill their urinals with ice cubes during peak hours. As the ice melts it serves to slowly flush the urinal, and also cools the urine to prevent smells from rising during use. The ice may also provide entertainment to patrons as they urinate. The Americans with Disabilities Act requires that flush valves be mounted no higher than 44" AFF. Additionally, the urinal shall be mounted no higher than 17" AFF, which has a rim that is tapered and elongated and protrudes at least 14" from the wall. This enables users in wheelchairs to straddle the lip of the urinal and urinate without having to "arc" the flow of urine too high.

Timed flush
In the UK, manual flush handles are unusual. Instead, the traditional system is a timed flush that operates automatically at regular intervals. Groups of up to ten or so urinals will be connected to a single overhead cistern, which contains the timing mechanism. A constant drip-feed of water slowly fills the cistern, until a tripping point is reached, the valve opens, and all the urinals in the group are flushed. Electronic controllers performing the same function are also used.

This system does not require any action from its users, but it is wasteful of water where the toilets are used irregularly. However, because British men are so used to the automatic system, attempts to install manual flushes to save water are generally unsuccessful. Users ignore them not through deliberate laziness or fear of infection, but because activating the flush is not included in their mental routine.

To help reduce water usage when restrooms are closed, some restrooms with timed flushing use an electric water valve connected to the restroom light switch. When the building is in active use during the day and the lights are on, the timed flush operates normally. At night when the building is closed, the lights are turned off and the flushing action stops.

Automatic flush
Toto battery-powered hands-free automatic sensor operated flush system. Electronic automatic flushes solve the problems of both previous approaches, and are common in new installations. Active or (more usually) passive infrared sensors identify when the toilet has been used, and activate the flush. Thus the urinal is cleaned where with a manual flush it might not have been, but water is not wasted when the toilet is not used.

Automatic flush facilities can be retro-fitted to existing systems. The handle-operated valves of a manual system can be replaced with a suitably-designed self-contained electronic valve, often battery-powered to avoid the need to add cables. Timed-flush installations may add a device that regulates the water flow to the cistern according to the overall activity detected in the room. This does not provide true per-fixture automatic flushing, but is simple and cheap to add because only one device is required for the whole system.

To prevent false-triggering of the automatic flush, most infra-red detectors require that a presence be detected for at least five seconds, such as when a person is standing in front of it. This prevents a whole line of automatic flush units from triggering in series if someone just walks past them.

The automatic flush mechanism also typically waits for the presence to go out of sensor range before flushing. This reduces water usage compared to a sensor that would trigger a continuous flushing action all the while a presence is being detected.

Door-regulated flush
This is an older method of water-saving automatic flushing, that only operates when the room is being used. A push-button switch is mounted in the door frame of the restroom, and triggers the flush valve for all restroom urinals every time the door is opened. While it can't detect the use of individual urinals, it provides reasonable flushing action without wasting excessive amounts of water when the restroom is not being used. This method requires a spring-operated automatic door closer, since the flush mechanism only operates when the restroom door opens.

Waterless urinals
A gutter urinal. A more recent innovation are urinals that do not use water at all. But uses a cartridge filled with a sealant liquid. The lighter than water sealant floats on top of the urine collected in the U-bend, preventing odors from being released into the air. The cartridge and sealant must be periodically replaced, but the system does save water and can be installed in situations where providing a water supply may be difficult or where water conservation is desired.

Waterless installations often include a label warning cleaning staff not to pour buckets of liquid into the urinal (to dispose of dirty mop water, for instance). A large influx of water would wash the sealant through the U-bend and down the drain, causing the urinal to smell until the sealant were replaced.