rule of thumb

noun phrase

Definition of rule of thumb

1 : a method of procedure based on experience and common sense
2 : a general principle regarded as roughly correct but not intended to be scientifically accurate

First Known Use of rule of thumb

circa 1658, in the meaning defined at sense 1

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The first known use of rule of thumb was circa 1658

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Cite this Entry

“Rule of thumb.” Dictionary, Merriam-Webster, Accessed 20 Sep. 2020.

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