\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

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 Instead, the onus should fall on outlets who hire critics. Yohana Desta, HWD, "Brie Larson Wants More Diverse Film Critics, Beyond Just “White Dudes”," 14 June 2018 But Spain will go on a deep run, too, and with an unconvincing set of strikers, the scoring onus will fall on the Real Madrid attacking midfield star. Si.com Staff, SI.com, "World Cup Crystal Ball: Russia 2018's Dark Horse, Breakout Star, Golden Boot and More," 5 June 2018 With an onus put on not crippling your teammates, the spring game generally favors the offense. OregonLive.com, "5 things to watch for the Oregon Ducks spring game," 20 Apr. 2018 My husband works long hours, and so the parental onus often fell heavily on me. Molly England, chicagotribune.com, "Managing an ongoing struggle with depression as a mother," 23 Mar. 2018 With the defense expected to suffer a drop-off this coming season, more of an onus will be placed on Daboll's successor to maximize Alabama's offensive talent. Rainer Sabin, AL.com, "Why Alabama's next OC hire will be critical for 'The Process'," 14 Jan. 2018 But when things go awry, regulators tend to put the onus on the apps, not the operating systems. Mark Gurman, Anchorage Daily News, "Apple cracks down on apps sharing information on users' friends," 12 June 2018 Although today’s officially atheist ruling Communist Party has no ideological baggage concerning LGTBQ lifestyles — unlike Islamic or Catholic nations, for instance — a strong Confucian influence puts a great onus on traditional families. Charlie Campbell / Shanghai, Time, "'We’ll Just Keep on Marching.' Tenth Shanghai Pride Spotlights China's Changing Attitudes Toward Gay Lifestyles," 15 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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Time Traveler for onus

The first known use of onus was in 1626

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English Language Learners Definition of onus

: the responsibility for something

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Comments on onus

What made you want to look up onus? Please tell us where you read or heard it (including the quote, if possible).


playful or foolish behavior

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