un·​rea·​son·​able | \ ˌən-ˈrēz-nə-bəl How to pronounce unreasonable (audio) , -ˈrē-zᵊn-ə-bəl\

Definition of unreasonable

1a : not governed by or acting according to reason unreasonable people
b : not conformable to reason : absurd unreasonable beliefs
2 : exceeding the bounds of reason or moderation working under unreasonable pressure

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Other Words from unreasonable

unreasonableness \ ˌən-​ˈrēz-​nə-​bəl-​nəs How to pronounce unreasonableness (audio) , -​ˈrē-​zᵊn-​ə-​bəl-​ \ noun
unreasonably \ ˌən-​ˈrēz-​nə-​blē How to pronounce unreasonably (audio) , -​ˈrē-​zᵊn-​ə-​blē \ adverb

Examples of unreasonable in a Sentence

I told him that I wouldn't pay unless he sent me a replacement. Am I being unreasonable? You are entitled to compensation for unreasonable delays.

Recent Examples on the Web

Under the Fourth Amendment’s protection from unreasonable searches and seizures, the police generally cannot enter a person’s home without a warrant. Michael Mccann, SI.com, "The Consequences Patrick Chung Could Face For His Felony Cocaine Charge," 22 Aug. 2019 Gun rights advocates warn red flag laws could violate the Fourth Amendment's prohibition on unreasonable searches and seizures, the 14th Amendment's due process clause and even the First Amendment. Kathryn Watson, CBS News, "Second Amendment advocates warn Trump over support for "red flag" laws," 14 Aug. 2019 The Fourth Amendment allows a person the right to protect themselves, their homes and their belongings from unreasonable searches. Lauren Castle, azcentral, "Arizonans have a right to privacy online, court rules," 31 July 2019 The lawsuit also argues that using electronic devices to monitor driver speeds and issue tickets on streets without a valid speed limit violates the 4th Amendment’s protection against unreasonable searches and seizures. Laura J. Nelson, Los Angeles Times, "L.A. police ticketed drivers on streets with expired speed limits, lawsuit says," 19 July 2019 The history of unreasonable violence itself is enough. Arash Javanbakht, The Conversation, "Can experts determine who might be a mass killer? 3 questions answered," 8 Aug. 2019 But the demands being made of them seemed increasingly unreasonable. Christine Biederman, WIRED, "Inside Backpage.com’s Vicious Battle With the Feds," 18 June 2019 To Nergaard, the suit seemed unreasonable: How could the group be supporting terrorism when the point of its workshops was to convince people to give up violence? Jenna Krajeski, The New Yorker, "A Victim of Terrorism Faces Deportation for Helping Terrorists," 11 June 2019 To many people, Piper can seem strikingly unreasonable. Thomas Chatterton Williams, New York Times, "Adrian Piper’s Show at MoMA is the Largest Ever for a Living Artist. Why Hasn’t She Seen It?," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unreasonable.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of unreasonable

14th century, in the meaning defined at sense 1a

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Last Updated

11 Sep 2019

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The first known use of unreasonable was in the 14th century

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English Language Learners Definition of unreasonable

: not fair, sensible, or appropriate : not reasonable


un·​rea·​son·​able | \ ˌən-ˈrē-zᵊn-ə-bəl How to pronounce unreasonable (audio) \

Kids Definition of unreasonable

: not fair, sensible, appropriate, or moderate an unreasonable schedule unreasonable behavior an unreasonable fear

Other Words from unreasonable

unreasonably \ -​blē \ adverb



Legal Definition of unreasonable

: not reasonable : beyond what can be accepted: as
a : clearly inappropriate, excessive, or harmful in degree or kind an unreasonable delay an unreasonable restraint of trade
b : lacking justification in fact or circumstance an unreasonable inference especially : irrational sense b the agency decision was unreasonable
c : not supported by a warrant or by a valid exception to a warrant requirement (as when there is reasonable suspicion) and therefore unconstitutional the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violatedU.S. Constitution amend. IV — see also search, seizure

Other Words from unreasonable

unreasonableness noun
unreasonably adverb

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Comments on unreasonable

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