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Definitions

rigorous

[rig-er-uhs] / ˈrɪg ər əs /
ADJECTIVE
severe; exact
Synonyms
STRONGEST
accurate brutal burdensome correct exacting harsh meticulous onerous precise proper rigid scrupulous strict stringent uncompromising
WEAK
ascetic austere bitter definite dogmatic hard inclement inflexible intemperate ironhanded nice oppressive punctilious right rugged stern stiff unpermissive
Antonyms
STRONGEST
careless false flexible gentle imprecise improper inaccurate incorrect inexact lenient negligent questionable soft tolerant unsuitable wrong yielding
WEAK
easygoing lax loose mild

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"I have never seen such a rigorous review process," Lutz said.

From Science Daily • Apr. 3, 2026

In Canada gun ownership is regulated by laws that require would-be gun owners to obtain a licence by passing a safety course and rigorous background checks before they can purchase a firearm.

From BBC • Apr. 3, 2026

Managers with experienced investment teams, rigorous underwriting standards and strong risk controls are structurally better positioned to navigate periods of stress.

From MarketWatch • Mar. 30, 2026

“This rigorous approach just hasn’t been taken with VSELs. I find the work mystifying and lacking in rigor,” he said.

From Slate • Mar. 30, 2026

Glenn’s training was very rigorous, including his physical fitness.

From "Reaching for the Moon" by Katherine Johnson

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.