[Latin — more at onerous]
: a disagreeable necessity : obligation
: blame
: stigma
[New Latin onus (probandi), literally, burden of proving] : burden of proof
put forth a theory that left the onus squarely on him

Did you know?

Understanding the etymology of onus shouldn’t be a burden; it’s as simple as knowing that English borrowed the word—spelling, meaning, and all—from Latin in the 17th century. Onus is also a distant relative of the Sanskrit word anas, meaning cart (as in, a wheeled wagon or vehicle that carries a burden). English isn’t exactly loaded with words that come from Latin onus, but onerous (“difficult and unpleasant to do or deal with”) is one, which is fitting since in addition to being synonymous with “burden,” onus has also long been used to refer to obligations and responsibilities that one may find annoying, taxing, disagreeable, or distasteful.

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
Recent Examples on the Web If Kendrick wanted to play football, the onus was on him to ask. Sam Cohn, Baltimore Sun, 13 Sep. 2023 But, Haley added, the onus is also on Senate Democrats to individually confirm the over 300 military nominations and promotions stuck in limbo, even though the confirmation process, Democrats say, would take up hours of precious floor time. Ken Tran, USA TODAY, 10 Sep. 2023 This would remove the onus of caring for an idiosyncratic work of architecture from city staff (who have other priorities) and the DTC (which can then focus on theater, not complex maintenance issues). Mark Lamster, Dallas News, 15 Aug. 2023 The onus is upon advertisers to properly categorize their own ads, but if Meta finds that the advertiser has miscategorized their ads, the company can remove them. WIRED, 1 Sep. 2023 Much of the onus this season falls on the shoulders of senior Ava Lambros, junior Sarah Farally and sophomore Sydney McLaughlin. Sam Cohn, Baltimore Sun, 31 Aug. 2023 Unlike hoaxes involving active shooters, bomb threats warrant a different response and the onus is on the school or business to decide whether a building should be evacuated. Cameron Knight, The Enquirer, 30 Aug. 2023 Regardless, García’s slump, Jung’s injury and Heim’s rust have created a clog in the heart of Texas’ lineups, one that’s put a great deal of the run-scoring onus onto batters further down the order. Shawn McFarland, Dallas News, 28 Aug. 2023 But the onus is really on the homeowner to point out these things. Rachel Kurzius, Anchorage Daily News, 26 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'onus.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1626, in the meaning defined at sense 1a

Time Traveler
The first known use of onus was in 1626


Dictionary Entries Near onus

Cite this Entry

“Onus.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/onus. Accessed 21 Sep. 2023.

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