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

Every credit card review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of credit card products. —Ryley Amond, CNBC, 16 Nov. 2025

The consensus is that AI tools should serve only as a starting point—subject to rigorous human verification—rather than as a substitute for qualified legal advice. —Megan Cartwright, MSNBC Newsweek, 15 Nov. 2025

In essence, Paris advocated for the executors to conduct themselves with a more rigorous sense of responsibility with respect to her father's moneyed estate. —Ryan Coleman, Entertainment Weekly, 14 Nov. 2025

Startups and established telehealth brands alike can benefit from this system, which could shorten launch cycles from months to weeks while maintaining rigorous clinical oversight. —Wyles Daniel, USA Today, 13 Nov. 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