rig·​or·​ous ˈri-g(ə-)rəs How to pronounce rigorous (audio)
: manifesting, exercising, or favoring rigor : very strict
: marked by extremes of temperature or climate
: scrupulously accurate : precise
rigorously adverb
rigorousness noun
Choose the Right Synonym for rigorous

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 The United States wants to limit the amount and purity of uranium Iran can enrich—thereby extending the time Tehran needs to produce enough fissile material to make a nuclear weapon—and to ensure that Iran’s nuclear program is subject to rigorous international monitoring. Maria Fantappie and Vali Nasr, Foreign Affairs, 20 Nov. 2023 His rigorous water polo training will certainly help in dealing with future boot camps. Eric Sondheimer, Los Angeles Times, 19 Nov. 2023 How is the expiration date determined for food products? Determining the expiration date for food products is a meticulous process rooted in scientific analysis and rigorous testing. Maeghan Dolph, Fox News, 19 Nov. 2023 The competition attracts contenders from around the world, who spend months of their lives going through rigorous training and preparation all in the hopes of coming out as the top dog dancing duo. Caroline Feller-Howard, ABC News, 17 Nov. 2023 Our take: As long as it’s based on rigorous analysis and not greenwashing, these kinds of prizes have an important signaling function for consumers, media, and executives. Bypeter Vanham, Fortune, 16 Nov. 2023 Lifton’s big books, though based on rigorous research, were written for popular audiences. Masha Gessen, The New Yorker, 12 Nov. 2023 The substance was identified using preliminary field tests, not more rigorous lab tests at FBI facilities, the official said. CBS News, 9 Nov. 2023 Post-Care For aftercare, Hamilton recommends avoiding saunas, hot baths, rigorous workouts, or anything that might make the skin too hot for the first day or so. Audrey Noble, Vogue, 11 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'rigorous.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

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

Dictionary Entries Near rigorous

Cite this Entry

“Rigorous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/rigorous. Accessed 7 Dec. 2023.

Kids Definition


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

More from Merriam-Webster on rigorous

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