onerous
Americanadjective
-
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.
KP Law added that some requests are "consistent with an intention to be onerous to the point of oppression" and ultimately stifle the litigation.
From BBC • Apr. 29, 2026
Still, many controllers opt out of what they describe as an onerous examination process that could culminate in losing their careers.
From The Wall Street Journal • Apr. 23, 2026
Recovering money after the fact is so much more onerous than intervening while it’s happening.
From MarketWatch • Mar. 30, 2026
Residents are criticizing a state law that requires permits and fees for building projects near Joshua trees, saying it’s opaque, confusing and onerous for those who want to improve or even maintain their properties.
From Los Angeles Times • Mar. 30, 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.
