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 of rigorous

• 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

Advocates for incarcerated people say the parole process is rigorous and shouldn’t be politicized. —Kate Wolffe, Sacbee.com, 11 Mar. 2026

More rigorous hiring standards that are aimed at academic improvement and start next year at a handful of campuses have also prompted shifts for some of those more than 1,450 employees. —Keri Heath, Austin American Statesman, 11 Mar. 2026

Every investing article is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of investment products. —Andreina Rodriguez, CNBC, 11 Mar. 2026

Under the Biden administration, a rigorous supporter of the agency, consumers’ rates of relief for such complaints rose to about 10 times as high as in 2020. —Joel Jacobs, CNN Money, 11 Mar. 2026

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