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
Judge Walgren’s responses to these allegations were measured and appropriate in the face of unsubstantiated allegations.
—
Rafael Perez, Daily News, 7 May 2026
Trump condemned Roberts and the five other justices who ruled against him on tariffs and made an unsubstantiated claim that the court was swayed by foreign interests.
—Andrew Chung, USA Today, 7 May 2026
The $250 million lawsuit alleged that the newspaper irresponsibly reported on Lively’s unsubstantiated allegations.
—Victoria Bekiempis, Vulture, 4 May 2026
The sites mix factual assertions about their targets with unsubstantiated conspiracies and defamatory claims of misconduct ranging from extortion and embezzlement to drug dealing and prostitution.
—Gary Baum, HollywoodReporter, 30 Apr. 2026
See All Example Sentences for unsubstantiated
Rafael Perez, Daily News, 7 May 2026
Trump condemned Roberts and the five other justices who ruled against him on tariffs and made an unsubstantiated claim that the court was swayed by foreign interests.
—Andrew Chung, USA Today, 7 May 2026
The $250 million lawsuit alleged that the newspaper irresponsibly reported on Lively’s unsubstantiated allegations.
—Victoria Bekiempis, Vulture, 4 May 2026
The sites mix factual assertions about their targets with unsubstantiated conspiracies and defamatory claims of misconduct ranging from extortion and embezzlement to drug dealing and prostitution.
—Gary Baum, HollywoodReporter, 30 Apr. 2026
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
-
Sterling failed to live up to unreasonable expectations created by his huge contract, which quickly became a millstone.—
Liam Twomey,
New York Times,
15 May 2026
-
The construction strikes many locals as both unreasonable and unstoppable.—
Rachel Monroe,
New Yorker,
14 May 2026
Adjective
-
In a statement to this news organization, the sheriff’s office said that probe concluded that the latter claims were unfounded.—
Robert Salonga,
Mercury News,
18 May 2026
-
The other two calls were canceled shortly after crews arrived or were determined to be unfounded.—
Kansas City Star,
Kansas City Star,
18 May 2026
Adjective
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Becerra said his rivals were making baseless claims because of his frontrunner status.—
Ben Paviour,
Sacbee.com,
15 May 2026
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Musk’s legal team accused Altman, OpenAI, and its president, Greg Brockman, of betraying the company’s founding mission, and OpenAI argued that Musk’s claims are baseless and aimed at gaining control over the company.—
David A. Graham,
The Atlantic,
14 May 2026
Adjective
-
Yeah, add that to the long list of unsupported claims about these vaccines that have ranged from various anti-vaxxers asserting that the vaccines will turn you into a gigantic magnet to attributing seemingly every celebrity illness and death during the COVID-19 pandemic to the COVID-19 vaccines.—
Bruce Y. Lee,
Forbes.com,
18 May 2026
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Tensions could rise around vulnerability, commitment or feeling emotionally unsupported, especially if someone’s actions don’t match their words.—
Valerie Mesa,
PEOPLE,
18 May 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 24 May. 2026.
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