rigorous

adjective

rig·​or·​ous ˈri-g(ə-)rəs 

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

• strict
• tough
• harsh
• authoritarian
• rigid
• stern

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

While the certification was not specifically a result of litigation, pursuing rigorous, third-party validation of AI practices is increasingly viewed as an industry best practice. —Marc Blythe, Forbes.com, 15 Aug. 2025

Every insurance article is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of insurance products. —Liz Knueven, CNBC, 15 Aug. 2025

Every member of the Minnesota Vikings Cheerleaders program has an impressive dance background and went through the same rigorous audition process. —Marni Rose McFall, MSNBC Newsweek, 15 Aug. 2025

But like populism’s critique of insider politics, the outsider critique of the medical establishment has always struggled to offer an alternative vision that’s rigorous rather than credulous. —Ross Douthat, Mercury News, 14 Aug. 2025

Word History

First Known Use

15th century, in the meaning defined at sense 1

Rhymes for rigorous

• vigorous

Kids Definition

rigorous

adjective

rig·​or·​ous ˈrig-(ə-)rəs 

1

: very strict

2

: marked by great differences of temperature or climate

3

: very accurate

rigorously adverb

rigorousness noun