\ ˈpləm How to pronounce plumb (audio) \

Definition of plumb

 (Entry 1 of 4)

: a lead weight attached to a line and used to indicate a vertical direction
out of plumb or off plumb
: out of vertical or true



Definition of plumb (Entry 2 of 4)

1 : straight down or up : vertically
2 chiefly dialectal : to a complete degree : absolutely 'you're plumb crazy', she remarked, with easy candorHarper's Weekly
3 : in a direct manner : exactly also : without interval of time : immediately


plumbed; plumbing; plumbs

Definition of plumb (Entry 3 of 4)

transitive verb

1 : to weight with lead
2a : to measure the depth of with a plumb
b : to examine minutely and critically plumbing the book's complexities
3 : to adjust or test by a plumb line
4 : to seal with lead
5 [back-formation from plumber] : to supply with or install as plumbing

intransitive verb

: to work as a plumber



Definition of plumb (Entry 4 of 4)

1 : exactly vertical or true

Choose the Right Synonym for plumb


vertical, perpendicular, plumb mean being at right angles to a base line. vertical suggests a line or direction rising straight upward toward a zenith. the side of the cliff is almost vertical perpendicular may stress the straightness of a line making a right angle with any other line, not necessarily a horizontal one. the parallel bars are perpendicular to the support posts plumb stresses an exact verticality determined (as with a plumb line) by earth's gravity. make sure that the wall is plumb

Examples of plumb in a Sentence

Adverb He set the board plumb. I plumb forgot about the party. Verb The book plumbs the complexities of human relationships. a scientist who spent her life plumbing the minds of criminals The play plumbs the depths of human nature. The plumber is almost finished plumbing the apartment. The new house has been wired and plumbed. All the bathroom fixtures have been plumbed. Adjective The carpenter made sure that the wall was plumb. a horror movie that's plumb trash and further evidence of the deterioration of popular culture
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Recent Examples on the Web: Noun Set the new prehung entry door into the opening from the outside (D), check it for plumb with a 4-ft. level on all sides, then tap shims between the doorframe and rough opening. Joseph Truini, Popular Mechanics, 28 Feb. 2021 That doesn’t mean an end to Shipt’s distinctive green - but the introduction of secondary colors such as plumb, yellow and teal. William Thornton |, al, 6 Feb. 2020 The Gallery of Kings—the line of statues above the three massive doorways—was almost a foot (.3 meters) out of plumb. Andrew Tallon, National Geographic, 16 Apr. 2019 In the olden days, woodworkers needed a range of measuring tools, plumbs and levels. Alexandra Samuel, WSJ, 14 Dec. 2018 The toppling tower inclined slowly to about fifteen feet out of plumb., 19 Mar. 2018 Hold each post plumb and drive nails through the anchors into the wood. Rick Peters, Popular Mechanics, 1 May 2016 Thankfully the technology used today has advanced beyond dangling plumb lines over the side of the ship. Kyle Frischkorn, Smithsonian, 13 July 2017 In other cases, the off-plumb spaces were turned into a narrow alley so that the rest of the parcel would have 90-degree corners. Richard Campanella,, 10 May 2017 Recent Examples on the Web: Verb The job of human resources is to assess our conduct, not to plumb our souls. New York Times, 4 Jan. 2022 When Kimmel/Lear decided to do a third installment of live episodes from the Lear canon of comedies, many assumed the pair would continue to plumb Lear’s more controversial, edgier library of work…perhaps Maude? Tom Nunan, Forbes, 9 Dec. 2021 Georgetown and Yale, for instance, have fully opened their archives to allow scholars to plumb their past involvement with slavery. Teresa Watanabe, Los Angeles Times, 14 Oct. 2021 But Gunn is able to plumb the depths of his character’s trauma for comedic effect as well, as evinced by Polka-Dot Man’s murderous fixation on his mother. Los Angeles Times, 6 Aug. 2021 Its actors are clearly doing their damnedest to plumb some depths in a mostly shallow pool. Jen Chaney, Vulture, 17 Aug. 2021 After every three or four courses, check that the wall is plumb [10]. Joseph Truini, Popular Mechanics, 24 July 2021 Gunn was able to plumb those depths to dig up the likes of Polka-Dot Man, Javelin, Blackguard, T.D.K., Savant, Ratcatcher 2, and King Shark (more formally known as Nanaue). Jacob Siegal, BGR, 9 Aug. 2021 Finally, a chance to plumb through the grim depths of A&E without needing to parse through any inscrutable genre tags! Luke Winkie, Vulture, 18 June 2021 Recent Examples on the Web: Adjective Taste: Oranges provide a brightness, plums plumb fruity depths, milk chocolate accounts for the richness and texture, while the strong smoky bottom layer is a combination of white pepper and soot that becomes medicinal. Felipe Schrieberg, Forbes, 27 Sep. 2021 The social credit system, a method of scoring people based on their behavior, could link child-rearing to bank loans or plumb jobs. Michael Schuman, The Atlantic, 1 July 2021 One of the hooks went plumb through his ring finger. John Goodspeed, San Antonio Express-News, 24 June 2021 That said, this trade helps bring the Falcons back into plumb, at least financially, and that matters. Arkansas Online, 8 June 2021 Tip the 4 x 4 post ends into the holes, and brace the screen so that the posts are plumb. Neal Barrett, Popular Mechanics, 15 May 2021 With a grey hull, many windows and plumb bow, the 105-footer from Arcadia Yachts was launched several months ago, and is now cruising the Caribbean. Michael Verdon, Robb Report, 14 Apr. 2021 But at least in Snyder’s version, Lois isn’t a woman who’s given up on life, spending her workdays gabbing with her dead lover’s mom and relinquishing plumb assignments to her less deserving colleagues. Kelsea Stahler,, 18 Mar. 2021 Guess Bigfoot and the Loch Ness Monster get all the plumb roles. René A. Guzman, San Antonio Express-News, 24 Feb. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'plumb.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of plumb


14th century, in the meaning defined above


15th century, in the meaning defined at sense 1


15th century, in the meaning defined at transitive sense 1


15th century, in the meaning defined at sense 1

History and Etymology for plumb


Middle English, from Anglo-French plum, plomb, from Latin plumbum lead

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Time Traveler for plumb

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The first known use of plumb was in the 14th century

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Cite this Entry

“Plumb.” Dictionary, Merriam-Webster, Accessed 24 Jan. 2022.

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More Definitions for plumb



English Language Learners Definition of plumb (Entry 2 of 3)

: exactly straight down or up : in a perfectly vertical position
: to a complete degree : completely



English Language Learners Definition of plumb (Entry 3 of 3)

: to examine (something) in a careful and complete way in order to understand it
: to experience or reach (something)
: to install pipes for sinks, toilets, etc., in (a building or room)



English Language Learners Definition of plumb (Entry 4 of 3)

: exactly vertical : standing perfectly straight and not leaning in any way


\ ˈpləm How to pronounce plumb (audio) \

Kids Definition of plumb

 (Entry 1 of 3)

: a small weight attached to a line and used to show depth or a straight vertical line


plumbed; plumbing

Kids Definition of plumb (Entry 2 of 3)

: to measure or test with a plumb They plumbed the depth of a well.



Kids Definition of plumb (Entry 3 of 3)

1 : exactly straight up and down
2 : completely I plumb forgot.

More from Merriam-Webster on plumb

Nglish: Translation of plumb for Spanish Speakers


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