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.
Saltman says a good rule of thumb is to just keep two to three linen sets per bed and two to three sets of towels per person. Tessa Cooper, The Spruce, 16 Apr. 2026 Mom should consider these rules of thumb when communicating with her future daughter-in-law. Nancy Mattia, Martha Stewart, 14 Apr. 2026 The traditional real estate industry rule of thumb has been that a seller's market is one with less than 4 months of supply of homes to buy, while a buyer's market is 6 months or greater. Andrea Riquier, USA Today, 10 Apr. 2026 The exact spacing varies according to the species and cultivar being grown, but a handy rule of thumb is to set low-growing hedge plants (3-4 feet tall) about two feet apart within rows. Kim Toscano, Southern Living, 9 Apr. 2026 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. 2026.

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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