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

The rule of thumb is well-known: Families are typically told to set aside three to six months’ worth of essential expenses to cover worst-case scenarios and other surprises.

From MarketWatch

I’m going to use the 4% rule because it’s a common rule of thumb.

From MarketWatch

This is where rules of thumb come into play — that you should have 10 times your current salary saved for retirement, or that you should spend 4% of your retirement portfolio each year in retirement.

From MarketWatch

As a rule of thumb, a payout ratio over 80% is considered risky.

From Barron's

For people planning to leave the workforce in their 60s, one rule of thumb is to set aside 15% of gross income for retirement.

From MarketWatch

Related Words

• criterion