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

The discovery of the solar cycle now moved Carrington to undertake a rigorous study of sunspots that soon earned him a reputation as Britain’s premier solar observer. —Literary Hub, 27 Oct. 2025

Every insurance review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of insurance products. —Alix Langone, CNBC, 27 Oct. 2025

So Zuriguel decided to take a more rigorous approach to the problem. —Ari Daniel, NPR, 27 Oct. 2025

That performance, plus a full offseason dedicated to rigorous strength workouts, has boosted her confidence. —Sean Gregory, Time, 27 Oct. 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