\ ˈō-nəs \

Definition of onus

1 [ Latin — more at onerous ]

a : burden
b : a disagreeable necessity : obligation
c : blame
d : stigma
2 [ New Latin onus (probandi), literally, burden of proving ] : burden of proof put forth a theory that left the onus squarely on him

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Did You Know?

Understanding the etymology of onus is not at all burdensome; it's as simple as knowing that English borrowed the word - spelling, meaning, and all - from Latin in the 17th century. We can also add that it's a distant relative of the Sanskrit word for "cart" (a vehicle that carries a burden). English isn't exactly loaded with derivatives of Latin onus, but the root did give us "onerous" ("troublesome") and "exonerate" ("to clear from accusation or blame" - thus, "to unburden"). Additionally, our legal language has "onus probandi," which is often shortened to "onus." It means "burden of proof" - that is, the obligation of proving a disputed assertion in a court of law.

Examples of onus in a Sentence

Consumers should be able to limit the use of information beyond what's essential to complete a transaction. There are two principal ways to do this: Web sites can permit them to "opt in," or explicitly grant advance permission to share information. Or they can put the onus on consumers to "opt out" if they don't want information shared. Consumer Reports, May 2000 These laws got the regulatory ball rolling, but the onus was on the U.S. Food and Drug Administration (FDA) to ensure that additives were safe. — Amy Rosenbaum Clark, Vegetarian Times, March 1995 It is not the scions of Yale and Harvard who apply to become FBI agents and construction workers and civil servants and cops who bear the onus of this reverse discrimination. — Thomas B. Edsall, Washington Post, 9-15 Mar. 1992 hoping to avoid the onus of failure by lowering expectations ahead of time he perpetually tries to shift the onus for any mistakes onto other team members
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Recent Examples on the Web

Outside much of the strict framework of regulation, Initial Coin Offerings put the onus on investors to perform their own due diligence, a task made more difficult by the apparent realism of fraudulent entities. Kevin Mcallister, WSJ, "Outsmart the Scammers: How You Can Avoid Fraud," 6 Jan. 2019 The Digital Economy Act was intended to be a more effective method of blocking adult sites that puts the onus on pornographers, who must comply with the policy or risk getting banned by major payment processors. Lux Alptraum, The Verge, "Online porn filters will never work," 26 Nov. 2018 That would put the onus on the three skeptical Republican senators: Sens. Emily Stewart, Vox, "Everything that’s happened since the Ford-Kavanaugh hearing, explained," 2 Oct. 2018 The onus is on the nonprofit organizations to put those tools... Eric Johnson, Recode, "Why nonprofits should think more like tech companies," 14 Nov. 2018 These facts are not hard to find, yet the onus is still on us—the victims—to try and prove rape culture exists and men benefit from it, some ascending to the highest positions of power in the country because of it. Danielle Campoamor, Marie Claire, "You’re Asking Why I Didn’t Report? Why Don’t You Ask Me Why I Regretted It When I Did?," 24 Sep. 2018 But remember that the onus is really on the doctor to navigate the situation properly, not you, Dr. Wise says. Sophie Saint Thomas, SELF, "Your Guide to Finding a Doctor Who Is an LGBTQ+ Ally," 14 Sep. 2018 That’s put the onus on retailers to hire the best seasonal workers as early as possible because those looking for work have considerable employment choices, analysts said. James F. Peltz, The Seattle Times, "Stores stock up early on seasonal workers," 24 July 2018 The onus, therefore, will fall on blockchain companies to ensure that the EU threshold for data ownership is met sufficiently. Zhuling Chen, Fortune, "How Should We Regulate Blockchain? It Depends on Which Country You Ask," 25 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'onus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of onus

1626, in the meaning defined at sense 1a

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Statistics for onus

Last Updated

19 Jan 2019

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Time Traveler for onus

The first known use of onus was in 1626

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More Definitions for onus



English Language Learners Definition of onus

: the responsibility for something

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More from Merriam-Webster on onus

Rhyming Dictionary: Words that rhyme with onus

Thesaurus: All synonyms and antonyms for onus

Spanish Central: Translation of onus

Nglish: Translation of onus for Spanish Speakers

Britannica English: Translation of onus for Arabic Speakers

Comments on onus

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tremendous in size, volume, or degree

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