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.
Once a month is a good rule of thumb, so water your lawn if there have been a few weeks without any rainfall. Karen Brewer Grossman, Southern Living, 11 Dec. 2025 But Flowers said his rule of thumb is for hunters to expect a third of the deer's total weight to be returned for consumption. Craig Shoup, Nashville Tennessean, 28 Nov. 2025 As a rule of thumb, pay off your balance on time and in full each month to avoid interest charges and keep your credit in good shape. Ryley Amond, CNBC, 27 Nov. 2025 While customs vary by destination, a good rule of thumb is $3 to $5 per night for standard hotels and $5 to $10 for luxury stays. Iona Brannon, Travel + Leisure, 25 Nov. 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 16 Dec. 2025.

Kids Definition

rule of thumb

1
: a method based on experience and common sense
2
: a general principle that is roughly correct
Last Updated: - Updated example sentences
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