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
-
The Fourth Amendment protects people against unreasonable searches and seizures.—
Eve Chen,
USA Today,
6 Feb. 2026
-
Those are clear violations of the Fourth Amendment’s safeguards against unreasonable searches and seizures, which were adopted to prevent the exercise of arbitrary government power.—
Yohuru Williams,
The Conversation,
4 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
-
Concerns about the validity of the ransom note are not unfounded.—
Hannah Fry,
Los Angeles Times,
9 Feb. 2026
Adjective
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Trump has repeatedly made baseless claims that there was voter fraud in the 2020 election, specifically in Georgia, that contributed to his election loss to Biden.—
Isabella Murray,
ABC News,
5 Feb. 2026
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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,
Chicago Tribune,
3 Feb. 2026
Adjective
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This came after unverified reports made unsupported claims about members of the Guthrie family.—
Larisha Paul,
Rolling Stone,
4 Feb. 2026
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The director puts a lot on her characters’ shoulders to illustrate how unsupported and isolated illness and disability can be.—
Lisa Kennedy,
Variety,
31 Jan. 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 13 Feb. 2026.
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