Definition of plumbing. the act of using a plumb. a plumber s occupation or trade. a the apparatus such as pipes and fixtures concerned in the distribution and use of water in a building. b an internal system that resembles plumbing especially one consisting of conduits or channels for conveying fluids..Specific meaning “water and drainage pipes” is recorded by , American English. THE apparatus by which the water from a reservoir is carried about over a building and delivered at points convenient for use, is called by the general name of plumbing..Plumbing is any system that conveys fluids for a wide range of applications. Plumbing uses . Media related to Plumbing at Wikimedia Commons The dictionary definition of plumbing at Wiktionary Quotations related to Plumbing at Wikiquote .Definition of plumbing the system of pipes, tanks, fittings, and other apparatus required for the water supply, heating, and sanitation in a building..Definition of plumbing written for English Language Learners from the Merriam Webster Learner s Dictionary with audio pronunciations, usage examples, and .