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
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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 measures are aimed at making both listing and staying listed in London cheaper and less onerous.
From The Wall Street Journal ● Aug. 10, 2026
Personally, I found probate less onerous than settling her estate without a will.
From MarketWatch ● Jul. 29, 2026
Falling numbers of workers spell yet another challenge for Europe's struggling top economy, already battling onerous red tape, high energy costs and fierce competition in its traditional industries.
From Barron's ● Jun. 15, 2026
As one of Jamaica's largest buyers of the fruit, for Gray's Pepper the shortages have been onerous.
From BBC ● May 31, 2026
This apparatus displayed Rutherford’s hallmark simplicity and style, but the procedure was unspeakably onerous.
From "Big Science" by Michael Hiltzik
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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.