unreasonable

adjective

un·​rea·​son·​able
ˌən-ˈrēz-nə-bəl,
-ˈrē-zᵊn-ə-bəl How to pronounce unreasonable (audio)
1
a
: 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
unreasonableness
ˌən-ˈrēz-nə-bəl-nəs
-ˈrē-zᵊn-ə-bəl- How to pronounce unreasonable (audio)
noun
unreasonably
ˌən-ˈrēz-nə-blē
-ˈrē-zᵊn-ə-blē How to pronounce unreasonable (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Courts will not second-guess the safety measures employers adopt, even when those measures infringe on an employee’s privacy, unless the measures are unreasonable under the circumstances. Dan Eaton, San Diego Union-Tribune, 21 Apr. 2025 Companies need to assess their higher costs, and then negotiate with the state regulators who try to protect ratepayers from unreasonable hikes. Camila Domonoske, NPR, 18 Apr. 2025 Spending has increased faster than revenue, and unreasonable budget estimates paint a rosier picture than reality demands. Andrew Rein, New York Daily News, 16 Apr. 2025 The logistics involved — eight shows a week, working (almost) every night — seemed unreasonable. Seija Rankin, HollywoodReporter, 15 Apr. 2025 See All Example Sentences for unreasonable

Word History

First Known Use

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

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

Browse Nearby Words

Cite this Entry

“Unreasonable.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreasonable. Accessed 26 Apr. 2025.

Legal Definition

unreasonable

adjective
un·​rea·​son·​able
: 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
unreasonableness noun
unreasonably adverb

More from Merriam-Webster on unreasonable

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!