What is the meaning of Plumbing?

The pipes, together with the joints, tanks, stopcocks, taps, and other fixtures of a water, gas, or sewage system in a house or other building.

The trade or occupation of a plumber.

A system of vessels or ducts in the human body, especially the genitourinary system.

Practical, concrete work serving to support other work.

A Murasugi sum where each disk summed along has its boundary subdivided into four segments.

Source: wiktionary.org