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Synonyms

unreasonable

American  
[uhn-ree-zuh-nuh-buhl, -reez-nuh-] / ʌnˈri zə nə bəl, -ˈriz nə- /

adjective

  1. not reasonable or rational; acting at variance with or contrary to reason; not guided by reason or sound judgment; irrational.

    an unreasonable person.

    Synonyms:
    silly, foolish, senseless
  2. not in accordance with practical realities, as attitude or behavior; inappropriate.

    His Bohemianism was an unreasonable way of life for one so rich.

    Synonyms:
    nonsensical, stupid, absurd, preposterous, silly, foolish, senseless
  3. excessive, immoderate, or exorbitant; unconscionable.

    an unreasonable price; unreasonable demands.

    Synonyms:
    extravagant
  4. not having the faculty of reason.


unreasonable British  
/ ʌnˈriːznəbəl /

adjective

  1. immoderate; excessive

    unreasonable demands

  2. refusing to listen to reason

  3. lacking reason or judgment

"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

  • unreasonableness noun
  • unreasonably adverb

Etymology

Origin of unreasonable

First recorded in 1300–50, unreasonable is from the Middle English word unresonabel. See un- 1, reasonable

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.

How should brands deal with negative comments or feedback, especially if the insults seem unjustified or unreasonable?

From The Wall Street Journal

California’s elderly parole program generally considers the release of prisoners who are older than 50 and have been incarcerated for at least 20 continuous years, considering whether someone poses an unreasonable risk to public safety.

From Los Angeles Times

He was not set upon by unreasonable hordes or ambushed by sneaky types.

From Literature

The inmate then can be released if the parole board determines they do not pose an unreasonable risk to public safety.

From Los Angeles Times

“If the conduct of the plaintiff in light of his own intelligence and information was manifestly unreasonable, he will be denied a recovery.”

From MarketWatch