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plumb bob


Simple Definition of plumb bob

  • : a usually small, heavy object that is used to make a string or rope hang straight : the heavy object that is part of a plumb line

Source: Merriam-Webster's Learner's Dictionary

Full Definition of plumb bob

  1. :  the metal bob of a plumb line

Circa 1840

First Known Use of plumb bob

circa 1840

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