plumber

Etymology

From Middle English plumber, from Old French plummier (French plombier); from Latin plumbārius, from plumbum (“lead or lead shot”).

noun

1. One who works in or with lead.
2. One who furnishes, fits, and repairs pipes and other apparatus for the conveyance of water, gas, or drainage.
   1. One who installs piping for potable and waste water.
3. A person who investigates or prevents leaks of information.
   It involved the break-in of the office of Mr. Lewis Fielding, Daniel Ellsberg's psychiatrist, by the White House “plumbers.” 1979, United States. Congress. House. Permanent Select Committee on Intelligence. Subcommittee on Legislation, Espionage Laws and Leaks: Hearings Before the Subcommittee...
4. (Britain, informal) In the Royal Navy, an apprentice, a boy aged 16 to 18, who is trained in technical skills at the Dockyard Schools to become an artificer.
5. (medicine, slang) A urologist.
   […] began the month with an operation at St. Joseph Hospital in Aurora, Ill. His surgeon, by the way, was a "plumber” – urologist. 1958, Father Provincial Assumption B.V.M. Monastery, The Chronicle, volumes 12-13, page 39
   Within surgery, the "cleaner" specialties, such as cardiac and neurosurgery, outrank the plumbers (urologists) and proctologists. 1983, Toni Martin, How to Survive Medical School, page 127