as in unreasonable
having no basis in reason or fact
an unsubstantiated claim that was thrown out of court
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Recent Examples of unsubstantiated
The mall was previously evacuated in years past for a nearby fire and an unsubstantiated threat.
—
Sarah Bahari, Dallas Morning News, 25 Mar. 2026
But unsubstantiated rumors of Netanyahu’s death continued to spread, with TikTokers and meme accounts analyzing subsequent posts from his account.
—Angela Yang, NBC news, 18 Mar. 2026
For years, unsubstantiated speculation circulated publicly tying Smith’s death to members of the Murdaugh family.
—Stepheny Price, FOXNews.com, 11 Mar. 2026
Hungarian Prime Minister Viktor Orbán doubled down Monday on an unsubstantiated claim that Ukraine is deliberately holding back shipments of Russian oil, and accused Kyiv of seeking to topple his government.
—Sam McNeil, Arkansas Online, 24 Feb. 2026
See All Example Sentences for unsubstantiated
Sarah Bahari, Dallas Morning News, 25 Mar. 2026
But unsubstantiated rumors of Netanyahu’s death continued to spread, with TikTokers and meme accounts analyzing subsequent posts from his account.
—Angela Yang, NBC news, 18 Mar. 2026
For years, unsubstantiated speculation circulated publicly tying Smith’s death to members of the Murdaugh family.
—Stepheny Price, FOXNews.com, 11 Mar. 2026
Hungarian Prime Minister Viktor Orbán doubled down Monday on an unsubstantiated claim that Ukraine is deliberately holding back shipments of Russian oil, and accused Kyiv of seeking to topple his government.
—Sam McNeil, Arkansas Online, 24 Feb. 2026
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
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Gill's decision came after Scott's lawyer requested to suspend the trial on the grounds that the grandparents had not met the state statute requiring them to prove Scott's decision to keep them from seeing Laila was unreasonable.—
Juliet Pennington,
PEOPLE,
24 Apr. 2026
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Keirans, 59, argued the 144-month prison term was unreasonable and that special conditions of supervised release were improper.—
CBS News,
CBS News,
24 Apr. 2026
Adjective
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An Amazon spokesperson said workers’ fears were unfounded.—
Greg Bensinger,
USA Today,
23 Apr. 2026
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Experts say those concerns are not unfounded.—
Larry Seward,
Miami Herald,
21 Apr. 2026
Adjective
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After Howard King was replaced for a time by attorney Mark Geragos, Geragos made a new but equally baseless $40 million demand on behalf of the Cascios.—
Cynthia Littleton,
Variety,
24 Apr. 2026
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The petition seeking a special prosecutor is frivolous, contains baseless allegations and gross misrepresentations of the law.—
Sabrina Franza,
CBS News,
24 Apr. 2026
Adjective
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What hurts me most is feeling unsupported by my partner.—
Abigail Van Buren,
Boston Herald,
30 Apr. 2026
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What becomes alarmingly evident through the key assumptions check is how many of the current responses expect a quick resolution of the conflict — a supposition that is unsound, or at least unsupported.—
Judd Devermont,
semafor.com,
27 Apr. 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 2 May. 2026.
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