rigorous

RIG-er-uss /ˈrɪɡərəs/
adjectiveC1GRESATGMATTOEFL
formalacademicscientific

Extremely thorough, exhaustive, or accurate.

Rigorous implies a level of strictness that leaves no room for error or laziness.

The story behind the word. The word comes from the Latin 'rigere', meaning 'to be stiff'. It is the same root as 'rigor mortis'. In a quality context, it means a process that is 'stiff' and 'unbending'—it does not allow for any deviation or softness.

Word relationships

  • stringent: Stringent refers to strict rules or requirements; rigorous refers to the thoroughness of the process.
  • lax: Lax means not sufficiently strict, severe, or careful.

Commonly confused with

  • vigorous: Vigorous means energetic and strong; rigorous means thorough and strict.

Word family

  • rigor (noun): The quality of being extremely thorough and careful.
  • rigorously (adverb): In an extremely thorough and careful way.

Collocations

  • rigorous testing
  • rigorous standards
  • rigorous analysis

Idioms & expressions

  • rigor of the law

Example sentences

  • "The most rigorous law is often the most rigorous injustice." Law
  • "The new drug underwent rigorous clinical trials before being approved for public use." Science

Memory hook

Rigorous is like 'Rigor-Us'—it makes 'us' follow the 'rigor' of the rules. Stiff adherence to the rules.

When not to use

Don't use 'rigorous' for something that is merely 'hard'; it specifically implies a systematic and disciplined approach.

Fun facts

  • In mathematics, a 'rigorous proof' is one that is logically complete and contains no gaps.
  • The word 'rigor' was first used in English in the 14th century to describe the 'stiffness' of a fever.

Related words

audit, tolerance, inspection

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