Definitions

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.

Of course, they’ll probably make it even more onerous so they can feel smart?

From Los Angeles Times • May 27, 2026

The watchdog said it did not think the requirements would be too onerous as services could decide to let trans people use toilets for disabled people, for example.

From BBC • May 21, 2026

A swap for cost basis planning looks even more advantageous when considering onerous tax rules for trust assets.

From Barron's • May 16, 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

This apparatus displayed Rutherford’s hallmark simplicity and style, but the procedure was unspeakably onerous.

From "Big Science" by Michael Hiltzik

Vocabulary lists containing onerous

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