What does "rule of thumb" mean?
What it means: A practical general guideline based on experience, not a precise rule. Something that works well enough in most situations without being formally calculated."As a rule of thumb, allow one hour per presentation slide.""The rule of thumb is to save three months of expenses."Where it ...
What it means
A practical general guideline based on experience, not a precise rule. Something that works well enough in most situations without being formally calculated.
"As a rule of thumb, allow one hour per presentation slide."
"The rule of thumb is to save three months of expenses."
Where it comes from
Various theories - carpenters measuring with their thumb, brewers testing temperature - but none are definitively proven. It's been in English since at least the 17th century.
What it implies
The guideline is approximate and practical, not guaranteed. "Rule of thumb" acknowledges that the real world is more complex but this works well enough for most cases.
A native would say
- "Generally speaking" - introducing a similar approximation
- "As a guideline" - formal version
- "Roughly" - simpler
- "A good ballpark is..." - similar approximate estimate
Register
Neutral. Works in professional and casual contexts.
What does "rule of thumb" mean?
A practical general guideline based on experience, not a precise rule. Something that works well enough in most situations without being formally calculated.
"As a rule of thumb, allow one hour per presentation slide."
"The rule of thumb is to save three months of expenses."
Is "rule of thumb" formal or informal?
Neutral. Works in professional and casual contexts.
What's another way to say "rule of thumb"?
- "Generally speaking" - introducing a similar approximation
- "As a guideline" - formal version
- "Roughly" - simpler
- "A good ballpark is..." - similar approximate estimate
Why do native speakers say "rule of thumb"?
Various theories - carpenters measuring with their thumb, brewers testing temperature - but none are definitively proven. It's been in English since at least the 17th century.
Idioms like this trip up even advanced learners.
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