the system of pipes and other apparatus for conveying water, liquid wastes, etc., as in a building.
the work or trade of a plumber.
act of a person who plumbs, as in ascertaining depth.

Origin of plumbing

First recorded in 1660–70; plumb + -ing1




a small mass of lead or other heavy material, as that suspended by a line and used to measure the depth of water or to ascertain a vertical line.Compare plumb line.

adjective Also plum.

true according to a plumb line perpendicular.
Informal. downright or absolute.

adverb Also plum.

in a perpendicular or vertical direction.
exactly, precisely, or directly.
Informal. completely or absolutely: She was plumb mad. You're plumb right.

verb (used with object)

to test or adjust by a plumb line.
to make vertical.
Shipbuilding. horn(def 32).
to sound with or as with a plumb line.
to measure (depth) by sounding.
to examine closely in order to discover or understand: to plumb someone's thoughts.
to seal with lead.
to weight with lead.
to provide (a house, building, apartment, etc.) with plumbing.

verb (used without object)

to work as a plumber.

Origin of plumb

1250–1300; Middle English plumbe, probably < Anglo-French *plombe < Vulgar Latin *plumba, for Latin plumbum lead
Related formsplumb·a·ble, adjectiveplumb·less, adjectiveplumb·ness, nounre·plumb, verb (used with object)un·plumb, adjective
Can be confusedplum plumb

Synonyms for plumb Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for plumbing

penetrate, explore, unravel, fathom, delve, sound, search, gauge, measure

Examples from the Web for plumbing

Contemporary Examples of plumbing

Historical Examples of plumbing

  • "There seems to be a leak in the plumbing somewhere on this floor," the man went on.

    The Film of Fear

    Arnold Fredericks

  • You may look over the plumbing in the bathroom whenever you are ready.

    The Film of Fear

    Arnold Fredericks

  • Constructions involved in the house, other than the plumbing fixtures.

    Rural Hygiene

    Henry N. Ogden

  • Leadership has improved its table manners, its plumbing, and its God.

    Erik Dorn

    Ben Hecht

  • And you know that it needs everything from plumbing to linen.


    Edna Ferber

British Dictionary definitions for plumbing



Also called: plumbery the trade or work of a plumber
the pipes, fixtures, etc, used in a water, drainage, or gas installation
the act or procedure of using a plumb to gauge depth, a vertical, etc



a weight, usually of lead, suspended at the end of a line and used to determine water depth or verticality
the perpendicular position of a freely suspended plumb line (esp in the phrases out of plumb, off plumb)

adjective Also: plum

(prenominal) informal, mainly US (intensifier)a plumb nuisance

adverb Also: plum

in a vertical or perpendicular line
informal, mainly US (intensifier)plumb stupid
informal exactly; precisely (also in the phrase plumb on)


(tr often foll by up) to test the alignment of or adjust to the vertical with a plumb line
(tr) to undergo or experience (the worst extremes of misery, sadness, etc)to plumb the depths of despair
(tr) to understand or master (something obscure)to plumb a mystery
to connect or join (a device such as a tap) to a water pipe or drainage system
Derived Formsplumbable, adjective

Word Origin for plumb

C13: from Old French plomb (unattested) lead line, from Old French plon lead, from Latin plumbum lead
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for plumbing

mid-15c., "the weighting of a fishing line," verbal noun from plumb (v.). Specific meaning "water and drainage pipes" is recorded by 1875, 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. The word "plumbing" means lead-work; and it is used to signify this water apparatus of a house because the pipes of which it largely consists are usually made of lead. [Edward Abbott, "Long Look House: A Book for Boys and Girls," Boston, 1877]

Alternative plumbery also is mid-15c. Slang meaning "a person's reproductive organs" attested by 1975.



"lead hung on a string to show the vertical line," early 14c., from Old French *plombe, plomee "sounding lead," and directly from Late Latin *plumba, originally plural of Latin plumbum "lead (the metal), lead ball; pipe; pencil," a word of unknown origin, related to Greek molybdos "lead" (dialectal bolimos) and perhaps from an extinct Mediterranean language, perhaps Iberian.



early 15c., "to sink" (like lead), from plumb (n.). Meaning "take soundings with a plumb" is first recorded 1560s; figurative sense of "to get to the bottom of" is from 1590s. Related: Plumbed; plumbing.



"perpendicular, vertical," mid-15c., from plumb (n.). The notion of "exact measurement" led to extended sense of "completely, downright" (1748), sometimes spelled plump, plum, or plunk.

Online Etymology Dictionary, © 2010 Douglas Harper