Word.ws English Dictionary

rules of thumb

rules of thumb is the plural of rule of thumb.

Meaning of rule of thumb

Noun

rule of thumb (plural rules of thumb)

  1. (idiomatic) A general guideline, rather than a strict rule; an approximate measure or means of reckoning based on experience or common knowledge.
    • The usual rule of thumb says that to calculate when an investment will double, divide 70 by the interest rate.
  2. (attributive, usually hyphenated) Approximated, guesstimated.
    • I made a quick, rule-of-thumb estimate of the manhours required for the job.

Questions about rules of thumb

What is rules of thumb the plural of?
Rules of thumb is the plural of rule of thumb.

Words near rules of thumb in the dictionary

  1. rules of decision
  2. rules of engagement
  3. rules of order
  4. rules of the game
  5. rules of the road
  6. rules of thumb
  7. rules off
  8. rules official
  9. rules OK
  10. rules on
  11. rules out

Source and license

Adapted from Wiktionary: rules of thumb (page history and authors); rule of thumb (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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Cite this entry: “rules of thumb.” Word.ws, https://word.ws/rules_of_thumb. Based on Wiktionary, CC BY-SA 4.0.