Simple Definition of plumb bob

from our Learner's Dictionary

plumb bob

noun

plural plumb bobs
US
1
: 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

called also bob

2

Cite this Entry

“Plumb bob.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/plumb%20bob. Accessed 15 Apr. 2026.

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