onus
Americannoun
plural
onuses-
a difficult or disagreeable obligation, task, burden, etc.
- Synonyms:
- load, duty, weight, responsibility
-
burden of proof.
-
blame or responsibility.
noun
Etymology
Origin of onus
1630–40; < Latin: load, burden
Explanation
Take the noun, onus, as a formal word for responsibility or obligation. If your teacher assigns onus as a vocabulary word, it puts the onus on you to find out what it means. Onus is a formal or sophisticated way to say "responsibility" or "duty." It sounds a little like the unrelated word owner, so think about the person with onus as owner of the responsibility. If the onus is on you to organize a fund raiser, you have to set the whole thing up. Have you ever heard the legal term onus probandi? It means the burden of proof, which requires the accuser to prove the case against the accused.
Vocabulary lists containing onus
100 SAT words Beginning with "O"
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The Freedom Writers Diary
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Lifting as We Climb
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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.
“Really, the onus should be on the government to make sure that our food is safe.”
From Salon • Apr. 11, 2026
“The onus is 100% on us to say: here is the value of being here,” said Remzi Arpaci-Dusseau, a professor of computer sciences at University of Wisconsin.
From The Wall Street Journal • Apr. 4, 2026
Ultimately, the onus is on you to ensure that the space is as comfortable and pleasing as possible, and that it matches the images in your listing.
From MarketWatch • Apr. 3, 2026
The defense put the onus for the violence on Crook.
From Los Angeles Times • Apr. 3, 2026
“Then on me be the onus of bringing it forward. Signior Eduardo, are you in voice to-night?”
From "Jane Eyre" by Charlotte Brontë
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
