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
Voting machine companies also have brought defamation cases against some conservative-leaning news sites that aired unsubstantiated claims about their equipment being linked to fraud in 2020.
—
Nicholas Riccardi, Los Angeles Times, 29 Jan. 2026
His specific claims are so far unsubstantiated — state investigators found daycares featured in the film operating as expected.
—Stephen Fowler, NPR, 16 Jan. 2026
The Kremlin looked to be doubling down on efforts to prolong the Ukraine war, making unsubstantiated claims that Kyiv had sought to attack one of Russian President Vladimir Putin’s residences, while Moscow’s forces launched a large-scale drone attack in southern Ukraine.
—Prashant Rao, semafor.com, 31 Dec. 2025
In 2024, the former Mesa County election clerk was sentenced for tampering with voting equipment to prove unsubstantiated voter fraud claims in 2020.
—David Zimmermann, The Washington Examiner, 31 Dec. 2025
See All Example Sentences for unsubstantiated
Nicholas Riccardi, Los Angeles Times, 29 Jan. 2026
His specific claims are so far unsubstantiated — state investigators found daycares featured in the film operating as expected.
—Stephen Fowler, NPR, 16 Jan. 2026
The Kremlin looked to be doubling down on efforts to prolong the Ukraine war, making unsubstantiated claims that Kyiv had sought to attack one of Russian President Vladimir Putin’s residences, while Moscow’s forces launched a large-scale drone attack in southern Ukraine.
—Prashant Rao, semafor.com, 31 Dec. 2025
In 2024, the former Mesa County election clerk was sentenced for tampering with voting equipment to prove unsubstantiated voter fraud claims in 2020.
—David Zimmermann, The Washington Examiner, 31 Dec. 2025
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
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There are people who desire to drastically improve the health of our ecosystems who unknowingly struggle with unreasonable expectations.—
Chris McKeown,
Cincinnati Enquirer,
14 Feb. 2026
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Amid those pressures, many people turn to the comfort of a pet – but the expectations for what dogs can bring to our lives are becoming increasingly unreasonable.—
Margret Grebowicz,
Fortune,
13 Feb. 2026
Adjective
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Public health experts also criticized the president for making unfounded claims about highly politicized health issues.—
Arkansas Online,
Arkansas Online,
9 Feb. 2026
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Concerns about the validity of the ransom note are not unfounded.—
Hannah Fry,
Los Angeles Times,
9 Feb. 2026
Adjective
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There are so many reasons to be mad; the mostly baseless and endless attacks on higher education, the dismantling of life-saving research, ICE, the subverting of policy that redresses shameful social harms.—
Wendy Nelson Espeland,
Mercury News,
11 Feb. 2026
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The Talmud teaches that Jerusalem was destroyed not only because of hatred, but because of sinat chinam, baseless hatred fueled by moral absolutism.—
Rabbi Bruce D. Forman,
Sun Sentinel,
10 Feb. 2026
Adjective
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But multiple flood events over the decades have continued to erode the older infrastructure, leaving parts of it unsupported.—
Dante Motley,
Austin American Statesman,
11 Feb. 2026
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But among the litany of possible adverse health outcomes listed, a new analysis in The Lancet published Thursday finds that 62 of those 66 risks are unsupported by reliable evidence.—
Elizabeth Cooney,
STAT,
5 Feb. 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 17 Feb. 2026.
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