onus
Americannoun
-
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.
“The onus is definitely on NextEra to show the value proposition and what’s in it for rate payers, and that’s important,” Bartlett said.
From The Wall Street Journal • May 19, 2026
The onus is on the creators to make the disclosure, but campaigns are required to tell them that they must do so.
From Los Angeles Times • May 15, 2026
"We have teams dedicated to limiting and combating misuse, but as with any technology, the onus is ultimately on individual people to not actively exploit it."
From BBC • May 13, 2026
He placed the onus for action on one’s conscience.
From Barron's • Apr. 14, 2026
Under the Sabotage Law, the onus was on the defense to prove the accused innocent.
From "Long Walk to Freedom" by Nelson Mandela
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.
