onerous

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

ADJECTIVE

difficult; requiring hard labor

Synonyms

STRONGEST

arduous backbreaking burdensome cumbersome demanding difficult distressing excessive exhausting grueling harsh intolerable laborious oppressive painful rigorous severe strenuous taxing troublesome weighty

WEAK

austere crushing embittering exacting exigent fatiguing formidable galling grave grinding hard headache heavy irksome merciless overpowering overtaxing plodding ponderous pressing responsible serious tiresome tiring toilsome vexatious

Antonyms

STRONGEST

calm easy effortless facile friendly gentle helpful mild nice simple trivial

WEAK

light

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.

One man, Walter Hunt, was the first to figure out how to make the work less onerous.

From The Wall Street Journal • Apr. 12, 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

Recovering money after the fact is so much more onerous than intervening while it’s happening.

From MarketWatch • Mar. 30, 2026

Other reforms include streamlining the process for collective Cabinet agreement of government policy, which are said to involve "onerous" exchanges of letters between departments.

From BBC • Mar. 25, 2026

“Oh, well, nothing at all onerous, I assure you,” said Scrimgeour.

From "Harry Potter and the Half-Blood Prince" by J.K. Rowling

Vocabulary lists containing onerous

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