rule of thumb

American  

noun

1. a general or approximate principle, procedure, or rule based on experience or practice, as opposed to a specific, scientific calculation or estimate.

2. a rough, practical method of procedure.

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rule of thumb British  

noun

1. 1. a rough and practical approach, based on experience, rather than a scientific or precise one based on theory

   2. ( as modifier )

      a rule-of-thumb decision

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rule of thumb Cultural  

1. A practical principle that comes from the wisdom of experience and is usually but not always valid: “When playing baseball, a good rule of thumb is to put your best hitter fourth in the batting order.”

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rule of thumb Idioms  

1. A rough and useful principle or method, based on experience rather than precisely accurate measures. For example, His work with the youth group is largely by rule of thumb. This expression alludes to making rough estimates of measurements by using one's thumb. [Second half of 1600s]

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Etymology

Origin of rule of thumb

First recorded in 1685–95

Example Sentences

Rule of thumb about US TV: all studios are smaller and all hosts are better looking than you expect, and Late Night with Seth Meyers ticks both of those boxes.

From The Guardian • Feb. 26, 2017

Rule of thumb: If Kanye is there, you’re probably in the right place.

From New York Times • May 4, 2015

Rule of thumb: more or less any premise is good for a film, and the supreme Hollywood master of melodrama, Douglas Sirk, was also the king of the ridiculous.

From The New Yorker • Mar. 16, 2015

Rule of thumb for filmmakers: If it's mundane in real life, it will be mundane on-screen.

From Los Angeles Times • Sep. 25, 2014

Rule of thumb: Get seven to nine hours of sleep total each day.

From Time • Aug. 1, 2014

Related Words

• criterion