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Synonyms

onerous

American  
[on-er-uhs, oh-ner-] / ˈɒn ər əs, ˈoʊ nər- /

adjective

  1. burdensome, oppressive, or troublesome; causing hardship.

    onerous duties.

    Synonyms:
    galling, irksome, grievous, heavy
  2. having or involving obligations or responsibilities, especially legal ones, that outweigh the advantages.

    an onerous agreement.


onerous British  
/ ˈəʊ-, ˈɒnərəs /

adjective

  1. laborious or oppressive

  2. law (of a contract, lease, etc) having or involving burdens or obligations that counterbalance or outweigh the advantages

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

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Vocabulary lists containing onerous

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.

Onerous regulations also make it needlessly difficult for us to treat the many patients for whom methadone is the best medication.

From Seattle Times • Aug. 8, 2023

Onerous local laws that require every gym and office, every sneaker store and Korean barbecue and donut shop, and most importantly every home to come with a certain number of parking spots.

From Slate • Sep. 16, 2022

Onerous and confusing reporting requirements can cause employed beneficiaries to lose their insurance anyway, as Arkansas learned last year.

From Washington Post • Dec. 12, 2019

Onerous, colonial-era laws against defamation and sedition mean frivolous cases can easily be registered with police, triggering years of expensive court proceedings.

From The Guardian • Dec. 31, 2017

Onerous as these terms were, the agreement came not a moment too soon.

From The Pirates of Malabar, and an Englishwoman in India Two Hundred Years Ago by Biddulph, J. (John)