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
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Into the Wild
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
The Legend of Sleepy Hollow
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
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.
Of course, they’ll probably make it even more onerous so they can feel smart?
From Los Angeles Times • May 27, 2026
He thinks the stock—a Barron’s pick —can report better-than-expected comparable sales, while investor expectations aren’t too onerous.
From Barron's • May 7, 2026
And if even that felt too onerous, they could console themselves that everyone is paying 1%, even the 10-year-old who made $100 selling lemonade.
From MarketWatch • May 7, 2026
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
“Oh, well, nothing at all onerous, I assure you,” said Scrimgeour.
From "Harry Potter and the Half-Blood Prince" by J.K. Rowling
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.
