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

Experimental adoption is fine, as long as it's paired with rigorous due diligence and clearly defined outcomes. —Stephanie Domas, Forbes.com, 27 June 2025

Hunting was off limits, as was trapping or poisoning, and the listing included rigorous habitat protections. —Christine Peterson, Vox, 27 June 2025

Every checking account review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of banking products. —Mia Taylor, CNBC, 27 June 2025

She’s also developed a rigorous skincare routine because her treatments leave her with chemotherapy rash. —Jillian Frankel, People.com, 27 June 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