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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.

He added that Ukraine’s request was “totally unreasonable and violates basic human rights.”

From The Wall Street Journal • May 3, 2026

Any detectable tonal noise, he added, must be considered an unreasonable threat to public health.

From Salon • Apr. 27, 2026

Does the 4th Amendment’s ban on unreasonable searches extend to your smartphone and its tracking data?

From Los Angeles Times • Apr. 27, 2026

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

“Would it be unreasonable of me to call you a genius?”

From "Adrift" by Paul Griffin

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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