UNREASONABLE Synonyms: 124 Similar and Opposite Words

unreasonable

adjective

ˌən-ˈrēz-nə-bəl

Definition of unreasonable

as in unwarranted

having no basis in reason or fact an unreasonable assumption

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in irrational

not using or following good reasoning an unreasonable respect for a man who did not deserve it

Synonyms & Similar Words

Antonyms & Near Antonyms

Example Sentences

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.

Recent Examples of unreasonable If Putin rejects the framework — or, more likely, demands unreasonable changes — then the world will at least know who blocked the fledgling peace effort. — David Ignatius, Washington Post, 21 Oct. 2026 This is not entirely unreasonable — earlier this year, CoreWeave secured its first investment-grade chip loan. — Elizabeth Lopatto, The Verge, 19 Oct. 2026 And the sense that Dodge had built something kind of unreasonable and then discovered that nobody tried to stop them. — New Atlas, 14 Oct. 2026 Judge Liman clearly considered the ‘outrageous and unreasonable’ $8 million plus demand and, in rejecting it, awarded only five percent of the amount sought in legal fees and costs. — Juliana Ukiomogbe, InStyle, 14 Oct. 2026 See All Example Sentences for unreasonable

Recent Examples of Synonyms for unreasonable

Adjective

His disparaging comments bemoaning the lack of financial support of UConn football by the state, UConn and Pratt & Whitney were totally unwarranted.

— Letters to the Editor, Hartford Courant, 29 Oct. 2026
Ashlee Jordan, a 29-year-old Bridgewater woman who was a former Title Clerk at the Quincy RMV, was charged with one count of bribery, one count of unwarranted privilege, and one count of conspiracy to commit title fraud.

— Matt Schooley, CBS News, 28 Oct. 2026

Definition of unwarranted

Adjective

Because the entire system is rewarded by doing more, investments in prevention are financially irrational.

— Paul Markovich, STAT, 2 Nov. 2026
There’s nothing irrational about voters demanding more from a state where a third of the work force is unemployed and ranks highest in the World Bank inequality index.

— Tiisetso Motsoeneng, semafor.com, 2 Nov. 2026

Definition of irrational

Adjective

The investigation was closed after authorities determined Thompson’s claims were unfounded, the department said.

— Elizabeth Campbell, Fort Worth Star-Telegram, 23 Oct. 2026
Stewart, a potent running quarterback for the Pittsburgh Steelers, was the talk of the industry when an unfounded rumor about him being gay threatened to derail everything.

— K. Thor Jensen, PC Magazine, 23 Oct. 2026

Definition of unfounded

Adjective

But in each event—in the living act, the undoubted deed—there, some unknown but still reasoning thing puts forth the mouldings of its features from behind the unreasoning mask.

— Literary Hub, Literary Hub, 6 July 2026
Roosevelt surely understood that nameless, unreasoning, unjustified fear cannot be eradicated.

— New York Times, New York Times, 9 June 2026

Definition of unreasoning

Adjective

Ethiopia’s Foreign Ministry rejected similar Sudanese accusations in a May 5 statement, calling them baseless, and accused Sudan of supporting rebels in its northern Tigray region.

— ABC News, ABC News, 4 Nov. 2026
The Central Elections Committee officially dismissed claims of widespread fraud as baseless and said there is no evidentiary basis for alleging a systematic compromise of the vote.

— Tal Shalev, CNN Money, 2 Nov. 2026

Definition of baseless

Adjective

Well, yes, this Court is an illegitimate Court on a number of levels.

— David Remnick, New Yorker, 30 Oct. 2026
Some people who file illegitimate disputes are simply looking to take advantage of the system and were never good customers to begin with.

— Arthur Zaczkiewicz, Footwear News, 30 Oct. 2026

Definition of illegitimate

Adjective

Its gravity is not measured by a relatively short list of maimings and deaths, nor can it be written off as perception unsupported by data.

— Justin Davidson, Curbed, 5 Nov. 2026
On the one hand, this shows just how strongly officers accept the principle of civilian control—a posture reinforced precisely because Hegseth has proved willing to punish even unsupported allegations of military insubordination.

— Peter D. Feaver, Foreign Affairs, 5 Nov. 2026

Definition of unsupported

Adjective

Ye Khaung Kyaw and the two other men charged in connection with the case have said the accusations against them are groundless.

— Arkansas Online, Arkansas Online, 24 Sep. 2026
Social media in South Korea have been filled with messages stoking fears about safety on Jeju, with some spreading groundless rumors and deriding the island.

— Hyung-Jin Kim, Los Angeles Times, 27 Aug. 2026

Definition of groundless

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unreason

unreasonable

unreasonableness

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Style

“Unreasonable.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unreasonable. Accessed 9 Nov. 2026.

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Synonyms of unreasonable

adjective

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