In plumbing, a sink or basin is a bowl-shaped fixture that is used for washing hands or small objects such as food, dishes, nylons, socks or underwear. In American plumbing parlance, a bathroom sink is known as a lavatory.

Sinks generally have taps (faucets) that supply hot and cold water and may include a spray feature to be used for faster rinsing. They also include a drain to remove used water; this drain may itself include a strainer and/or shut-off device and an overflow-prevention device. Sinks may also have an integrated soap dispenser.

When a sink becomes stopped-up or clogged, a person will often resort to use of chemical drain cleaner or a plunger, though most professional plumbers will attack the clog with a drain auger (often called a "plumber's snake").

Materials

Sinks are made of many different materials. These include:

• Stainless steel
• Enamel over steel or cast iron
• Ceramic
• Plastic
• Soapstone
• Concrete
• Terrazzo
• Totianota
• Wood
• Stone
• Copper
• Glass

Stainless steel is commonly used in kitchens and commercial applications because it represents a good trade-off between cost, usability, durability, and ease of cleaning. Most stainless steel sinks are made by drawing a sheet of stainless steel over a die. Some very deep sinks are fabricated by welding. Stainless steel sinks will not be damaged by hot or cold objects and resist damage from impacts. One disadvantage of stainless steel is that, being made of thin metal, they tend to be noisier than most other sink materials, although better sinks apply a heavy coating of vibration-damping material to the underside of the sink.

Enamel over cast iron is a popular material for kitchen and bathroom sinks. Heavy and durable, these sinks can also be manufactured in a very wide range of shapes and colors. Like stainless steel, they are very resistant to hot or cold objects, but they can be damaged by sharp impacts and once the glass surface is breached, the underlying cast iron will often corrode, spalling off more of the glass. Aggressive cleaning will dull the surface, leading to more dirt accumulation. Enamel over steel is a similar-appearing but far less rugged and less costly alternative.

Solid ceramic sinks have many of the same characteristics as enamel over cast iron, but without the risk of surface damage leading to corrosion.

Plastic sinks come in several basic forms:

• Inexpensive sinks are simply injection-molded thermoplastics. These are often deep, free-standing sinks used in laundry rooms. Subject to damage by hot or sharp objects, the principal virtue of these sinks is their low cost.