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.
The school also looks at ways to ensure everyone has access to rigorous instruction. — Michelle Mullins, Chicago Tribune, 22 Oct. 2026 Researchers say the approach could make rigorous software verification practical for a much wider range of projects. — Aamir Khollam, Interesting Engineering, 22 Oct. 2026 Like SpaceX and Tesla CEO Elon Musk, many founders in tech have moonshot performance pay packages, in which rigorous stock price growth is tied to massive pay hurdles. — Amanda Gerut, Fortune, 21 Oct. 2026 Every nonprofit bank account list is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of business banking products. — Andreina Rodriguez, CNBC, 21 Oct. 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
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Cite this Entry

“Rigorous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rigorous. Accessed 24 Oct. 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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