rigorous

adjective

rig·​or·​ous ˈri-g(ə-)rəs How to pronounce rigorous (audio)
Synonyms of rigorous
1
: manifesting, exercising, or favoring rigor : very strict
2
a
: marked by extremes of temperature or climate
b
: harsh, severe
3
: scrupulously accurate : precise
rigorously adverb
rigorousness noun

Synonyms of rigorous

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rigid, rigorous, strict, stringent mean extremely severe or stern.

rigid implies uncompromising inflexibility.

rigid rules of conduct

rigorous implies the imposition of hardship and difficulty.

the rigorous training of recruits

strict emphasizes undeviating conformity to rules, standards, or requirements.

strict enforcement of the law

stringent suggests severe, tight restriction or limitation.

stringent standards of admission

Examples of rigorous in a Sentence

rigorous enforcement of the rules a rigorous course of study We subjected the data to a rigorous analysis.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Experts advocate rigorous testing, staged deployment, comprehensive logging, and addressing fundamental security issues. — Sandy Carter, Forbes.com, 2 Aug. 2026 In a bit of irony, Jassy’s rigorous comments Thursday night took up all the hyperscalers’ stocks in Friday’s session. — Jim Cramer, CNBC, 2 Aug. 2026 Academy leaders have repeatedly told Congress that rigorous scholarship, civilian faculty expertise and exposure to complex questions help prepare officers for the uncertainty of modern warfare. — James Laporta, CBS News, 31 July 2026 The progress marks the transition from years of design, research, and technology demonstrations to the construction of physical aircraft that will undergo rigorous testing before entering operational service. — Prabhat Ranjan Mishra, Interesting Engineering, 31 July 2026 See All Example Sentences for rigorous

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of rigorous was in the 15th century

Rhymes for rigorous

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Browse Nearby Words

rigor mortis
rigorous
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Cite this Entry

“Rigorous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rigorous. Accessed 5 Aug. 2026.

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Kids Definition

rigorous

adjective
rig·​or·​ous ˈrig-(ə-)rəs How to pronounce rigorous (audio)
1
: very strict
2
: marked by great differences of temperature or climate
3
: very accurate
rigorously adverb
rigorousness noun

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