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
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
Hungarian Prime Minister Viktor Orbán doubled down Monday on an unsubstantiated allegation that Ukraine is deliberately holding back shipments of Russian oil, and accused Kyiv of seeking to topple his government.
—ABC News, 23 Feb. 2026
See All Example Sentences for unsubstantiated
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
Hungarian Prime Minister Viktor Orbán doubled down Monday on an unsubstantiated allegation that Ukraine is deliberately holding back shipments of Russian oil, and accused Kyiv of seeking to topple his government.
—ABC News, 23 Feb. 2026
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
-
Indeed, because deportation is not considered a criminal matter, the constitutional provisions protecting those accused and convicted of crimes do not apply, including prohibiting unreasonable searches and seizures, providing a lawyer and requiring a jury trial.—
Erwin Chemerinsky,
Twin Cities,
8 Apr. 2026
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That has prompted constitutional concerns around the Fourth Amendment, which prevents unreasonable search and seizure.—
Lisa Hagen,
Hartford Courant,
7 Apr. 2026
Adjective
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Coachella sold out with record spending from fans, and fears that ICE might show up for a prominent Latin headliner proved unfounded.—
Los Angeles Times,
Los Angeles Times,
19 Apr. 2026
-
Valentine did not return phone calls on Thursday, but Lavelle said the board hired an investigator to look into the first complaint, which was determined to be unfounded.—
Andy Sheehan,
CBS News,
16 Apr. 2026
Adjective
-
Prosecutors looking to strip Eastman of his law license had depicted him as fabricating a baseless theory and making false claims of fraud in hopes of overturning the results of the election.—
ABC News,
ABC News,
15 Apr. 2026
-
Gregg Phillips, a far-right conspiracy theorist who has been previously cited by the president for his baseless claims about fraud in the 2020 presidential election, was tapped to lead FEMA’s Office of Response and Recovery in December 2025.—
Meredith Kile,
PEOPLE,
14 Apr. 2026
Adjective
-
Past experiences of being overlooked, criticized, or unsupported may come up today.—
USA TODAY,
USA Today,
16 Apr. 2026
-
The lawsuit is reckless, irresponsible, and completely, completely, unsupported by the facts of this case.—
Jeff Capellini,
CBS News,
7 Apr. 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 22 Apr. 2026.
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