plumb line

noun

1
: a line (as of cord) that has at one end a weight (such as a plumb bob) and is used especially to determine verticality
2
: a line directed to the center of gravity of the earth : a vertical line

Examples of plumb line in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Instead of standing with the verticality of a plumb line, there’s a slight arc to my torso. John Haskell, Harpers Magazine, 20 Aug. 2025 His dedication to the integrity of his craft runs like a plumb line through his career. Wendell Steavenson, Vogue, 5 Jan. 2025 The vertical distance from the front tip of a stair nosing to the top of the railing in a plumb line should be between 34 and 38 inches. Tim Carter, Hartford Courant, 30 Nov. 2024 No one knew what kinda plumb line–astrolabe–compass had brought them to land. Lawrence Jackson, Harper's Magazine, 10 July 2023 Conceived around the simple concept of a plumb line, the pieces play with the house’s signature use of negative space, with typical restraint. Sarah Royce-Greensill, Robb Report, 27 Jan. 2023 Every two weeks, a dam employee enters one of the four concrete intake towers and lowers a plumb line down to the water level to take an exact measurement. Joshua Partlow, Anchorage Daily News, 29 June 2022 Since that's often not the case, Rees recommends drawing a plumb line, basically a guideline to ensure your wallpaper is aligned. Hadley Keller, House Beautiful, 4 Dec. 2020

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of plumb line was in the 15th century

Browse Nearby Words

Cite this Entry

“Plumb line.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/plumb%20line. Accessed 3 Jul. 2026.

Kids Definition

plumb line

noun
: a line that has a weight (as a plumb bob) at one end and is used to find out whether something is vertical or to measure depth

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