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
Overwhelmingly, those cases stem from reports later found to be false or unsubstantiated.
—
James R Mason, Hartford Courant, 12 May 2026
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
See All Example Sentences for unsubstantiated
James R Mason, Hartford Courant, 12 May 2026
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
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
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However, investing in public institutions and infrastructure is a costly endeavor that can seem unreasonable when local officials are struggling to balance budgets without increasing tax burdens.—
Aneri Pattani,
USA Today,
6 June 2026
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Nineteen recent clinical trials on kratom leaf document no evidence of severe addiction or significant or unreasonable adverse effects.—
Tara Molina,
CBS News,
1 June 2026
Adjective
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Many Peruvians accuse her of being a bad loser, who for months refused to acknowledge her loss in 2016 and then made unfounded accusations of electoral fraud in 2021.—
Simeon Tegel,
NPR,
6 June 2026
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That is huge considering how badly cyber stocks had sold off earlier in the year on what Jim Cramer said all along were unfounded disruption concerns.—
Morgan Chittum,
CNBC,
6 June 2026
Adjective
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State officials and elections experts reject the allegations as baseless, pointing to California’s generous mail voting rules, laborious signature checks and a predictable ‘red mirage’ that initially favors Republicans.—
Kevin Rector,
Los Angeles Times,
4 June 2026
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Cook rejected the charges as baseless, calling them politically motivated.—
Max Zahn,
ABC News,
1 June 2026
Adjective
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According to the report, 71% of those who felt unsupported on productions said safety policies weren’t properly followed.—
Max Goldbart,
Deadline,
28 May 2026
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Many influencers lack formal nutrition credentials and promote unsupported health claims.—
LeeAnn Weintraub,
Oc Register,
27 May 2026
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 10 Jun. 2026.
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