rule of thumb

noun phrase

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

Examples of rule of thumb 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.
The data show the issue is more complicated than the rule of thumb. Bob Carlson, Forbes.com, 22 Apr. 2025 The rule of thumb is to make sure there is room for adequate airflow around the machine, which means keeping it at least 6 inches away from walls and furniture or any other obstructions that may inhibit airflow. Bestreviews, Chicago Tribune, 14 Apr. 2025 Avid Travel + Leisure readers already know that this rule of thumb also applies to build-it-yourself tiny homes. Amelia McBride, Travel + Leisure, 25 Mar. 2025 The rule of thumb for eating more fiber is to go slow, make one change at a time and drink plenty of fluids. Hannah Yasharoff, USA TODAY, 21 Mar. 2025 See All Example Sentences for rule of thumb

Word History

First Known Use

circa 1658, in the meaning defined at sense 1

Time Traveler
The first known use of rule of thumb was circa 1658

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Cite this Entry

“Rule of thumb.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rule%20of%20thumb. Accessed 29 Apr. 2025.

Kids Definition

rule of thumb

1
: a method based on experience and common sense
2
: a general principle that is roughly correct
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