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 paddlers selected for the Klamath journey completed a rigorous three-year regimen, starting with a two-and-a-half-week kayak and river advocacy training program for 15 Indigenous youths from the Klamath Basin, followed by weekend kayaking trips and kayak roll training. —Debra Utacia Krol, USA Today, 2 Sep. 2025

The components are chemically identical to those made from petroleum, a crucial detail for industries with rigorous safety standards. —Afdhel Aziz, Forbes.com, 1 Sep. 2025

Training was rigorous and deadly. —Brad Lendon, CNN Money, 1 Sep. 2025

Every credit card review is based on rigorous reporting by our team of expert writers and editors with extensive knowledge of credit products. —Ryley Amond, CNBC, 1 Sep. 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