onerous
American
adjective
-
laborious or oppressive
-
law (of a contract, lease, etc) having or involving burdens or obligations that counterbalance or outweigh the advantages
Other Word Forms
Etymology
Origin of onerous
1350–1400; Middle English < Latin onerōsus, equivalent to oner- (stem of onus ) burden + -ōsus -ous
Explanation
If one teacher gives you three hours of homework a night, that's rough. But if all of your teachers do it, that makes the task of completing your homework an onerous one, to say the least. If something is onerous, it is very difficult to deal with or do. A near synonym is burdensome. In legal usage, onerous describes a contract or lease that has more obligations than advantages. Onerous derives from Middle English, from Old French onereus, from Latin onerōsus, from onus "burden." In English, an onus is a task or duty that is onerous, or very difficult.
Vocabulary lists containing onerous
300 Most Difficult "SAT" Words
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Into the Wild
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The Legend of Sleepy Hollow
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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.
Northern Star said the Gold Fields bid was subject to several onerous conditions and requirements, and that a deal would have exposed its shareholders to jurisdictional and operational risks given its significant equity component.
From The Wall Street Journal ● Sep. 28, 2026
Francesca said the justice system had let a lot of people down, including Karol's five children, the wider family and the jury at the trial who listened to "thorough, onerous and sometimes difficult evidence".
From BBC ● Sep. 22, 2026
Some local business owners urged the council to reject the ordinance, saying the resulting added costs would be onerous and unnecessary.
From Los Angeles Times ● Sep. 8, 2026
Personally, I found probate less onerous than settling her estate without a will.
From MarketWatch ● Jul. 29, 2026
This apparatus displayed Rutherford’s hallmark simplicity and style, but the procedure was unspeakably onerous.
From "Big Science" by Michael Hiltzik
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.
