Pronunciation: [bˈɔːlkɒk] (IPA) 
The word "ballcock" is spelled with two L's, rather than one as in "cocktail". This is because the first syllable of "ball" is stressed, which means that the vowel sound is pronounced with more emphasis. In IPA phonetic transcription, the first syllable of "ball" is represented as /bɔːl/, with a longer and more open "o" sound than in "cocktail" (/kɒkteɪl/). This emphasis on the first syllable gives "ballcock" its unique spelling.
A ballcock is a mechanical device or valve used in a toilet cistern to control the flow of water and maintain the desired water level. It is typically a small, spherical or cylindrical float attached to an arm or rod. The ballcock is connected to the water supply and is responsible for regulating the water flow into the cistern.
The mechanism of a ballcock operates through buoyancy principles. When the water level drops in the cistern after a flush, the ballcock float also descends. This movement causes the arm or rod to rotate, which in turn opens a valve at the bottom of the cistern allowing fresh water to flow in. As the water level rises, the float ascends, and once the desired level is reached, the valve is closed, preventing any further water from entering.
The term "ballcock" comes from the shape of the float which was historically made from a hollow ball. Nowadays, the float can also be designed as a cylinder or other shapes. While ballcocks were traditionally made of brass, modern versions are commonly constructed of plastic or other materials.
Ballcocks have become a standard component in most household toilets, providing a reliable method to regulate water levels and facilitate efficient flushing. They are essential for maintaining the proper functioning of a toilet by ensuring a consistent water supply while preventing overflows or water wastage.
The word "ballcock" has a rather straightforward etymology. It is a combination of two main components: "ball" and "cock".
The term "ball" refers to a spherical object, and in this context, it refers to a small sphere or ball within the mechanism of the ballcock itself.
The word "cock" in this context comes from the Old English word "cocc", which originally meant a stopper or plug for a container. Over time, "cock" began to specifically refer to the stopper or valve used to regulate the flow of liquid, especially in plumbing systems.
Therefore, the combination of "ball" and "cock" in "ballcock" refers to the specific mechanism used in plumbing systems to control the flow of water in a toilet tank.
