plumb line


noun

a cord with a lead bob attached to one end, used to determine perpendicularity, the depth of water, etc.Compare plumb(def 1).

Origin of plumb line

First recorded in 1530–40
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

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British Dictionary definitions for plumb line

plumb line

noun

a string with a metal weight at one end that, when suspended, points directly towards the earth's centre of gravity and so is used to determine verticality, the depth of water, etc
another name for plumb rule
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

Scientific definitions for plumb line

plumb line
[ plŭm ]

A line regarded as directed exactly toward the Earth's center of gravity.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.