Word.ws English Dictionary

rule of three

rule of three proper noun: a rule stating that, if two ratios are equal, then the denominator of the second equals its numerator times the reciprocal of the first ratio: if a/b=c/d then d=(bc)/a.

Proper noun (1)

the rule of three

  1. A rule stating that, if two ratios are equal, then the denominator of the second equals its numerator times the reciprocal of the first ratio: if a/b=c/d then d=(bc)/a.
    • Multiplication is vexation, / Division is as bad; / The Rule of Three doth puzzle me, / And Practice drives me mad.1886, James Orchard Haliwell, The Nursery Rhymes of England, 5th edition, page 78
  2. A rule for clinical trials used for determining the rate of adverse side effects when no such side effects present during the course of the trial.
  3. (rhetoric) A rule which states that things which come in groups of three are inherently funnier or more effective than things which come in groups of other sizes.
    1. (rhetoric) Specifically, the technique of having a setup in advance, a reminder to keep it fresh in the audience's memory, and then a payoff.
  4. A religious tenet stating that the energy a person puts out into the world, positive or negative, will be returned to that person threefold.
  5. A rule of thumb in the C++ programming language, stating that any class that defines a destructor, a copy constructor, or a copy assignment operator should define all three of them.
  6. (survival) A mnemonic guideline that outlines the average limits of human endurance.

Proper noun (2) capitalized: Rule of Three

the Rule of Three

  1. Alternative letter-case form of rule of three (sense 4); a religious tenet held by some Wiccans, stating that whatever energy, positive or negative, a person puts into the world will be returned threefold.
    Synonyms:
    karma, golden rule

rule of three meaning in Tagalog

rule of three in Tagalog

mathematical rule
tuntunin ng tatlo

Synonyms of rule of three

Forms of rule of three

alternative formthe Rule of Three
alternative formthe rule of threes
alternative formthe Three-Fold Law
alternative formthe Law of Return

Questions about rule of three

What does rule of three mean?
Rule of three means a rule stating that, if two ratios are equal, then the denominator of the second equals its numerator times the reciprocal of the first ratio: if a/b=c/d then d=(bc)/a.
What is rule of three in Tagalog?
Rule of three in Tagalog is tuntunin ng tatlo. See Rule of three meaning in Tagalog.
What part of speech is rule of three?
Rule of three is a proper noun.

Words near rule of three in the dictionary

  1. rule of strict construction
  2. rule of succession
  3. rule of the road
  4. rule of the shorter term
  5. rule of thirds
  6. rule of three
  7. rule of threes
  8. rule of thumb
  9. rule of tincture
  10. rule of two
  11. rule off

Source and license

Adapted from Wiktionary: rule of three (page history and authors); Rule of Three (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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