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Definitions

unreasonable

[uhn-ree-zuh-nuh-buhl, -reez-nuh-] / ʌnˈri zə nə bəl, -ˈriz nə- /
ADJECTIVE
not logical or sensible
Synonyms
STRONGEST
absurd arbitrary biased contradictory foolish illogical inconsistent irrational preposterous senseless silly stupid wrong
WEAK
all wet capricious erratic fallacious far-fetched full of hot air headstrong incoherent incongruous inconsequential invalid loose mad nonsensical off the wall opinionated quirky reasonless thoughtless unreasoned vacant
Antonyms
STRONGEST
circumspect consistent correct intelligent logical rational reasonable right sensible serious wise
WEAK
cheap economical low plain practical pragmatic realistic
ADJECTIVE
extravagant; beyond normal limits
Synonyms
STRONGEST
arbitrary excessive exorbitant extreme illegitimate improper inordinate senseless unconscionable undue unfair unjust unjustifiable unlawful unwarranted wrongful
WEAK
absonant costing an arm and a leg dear extortionate far-out immoderate intemperate out of bounds overkill overmuch peremptory posh pricey steep stiff too great too much too-too uncalled-for unrightful unwarrantable up to here way-out
Antonyms
STRONGEST
authorized decent ethical fair good just justifiable legal moderate moral rational reasonable right sensible unprejudiced warranted
WEAK
cheap economical logical low plain practical pragmatic realistic

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.

Tehran has said it will not attend because of what it said were unreasonable US demands, while the semi-official Tasnim news agency said there was no prospect of officials going at present.

From Barron's • Apr. 22, 2026

Usually, when a story isn't right or has perhaps leapt to conclusions seen to be unreasonable, my phone will be ringing in seconds.

From BBC • Apr. 16, 2026

In 1971, the Supreme Court began to patch this hole in a case called Bivens, approving monetary damages against federal agents who violated the Fourth Amendment’s guarantee against unreasonable search and seizure.

From Slate • Apr. 15, 2026

It’s not unreasonable for drivers to be upset about high fuel prices and for policymakers to want to tackle the issue.

From MarketWatch • Apr. 1, 2026

He implies she is being unreasonable, but that to deny her this thing, this too-expensive toy, wounds him deeply just the same.

From "Cat's Eye" by Margaret Atwood

Vocabulary lists containing unreasonable

"The Southpaw"

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Chronically Dolores

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Part 3 Vocabulary (Unit 2)

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