as in unreasonable
having no basis in reason or fact
an unsubstantiated claim that was thrown out of court
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Example Sentences
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Recent Examples of unsubstantiated
For the past several months, Owens has waged a digital terror campaign against Erika Kirk, spreading conspiracy theories about her husband’s death (and appearing to imply that Erika was involved in covering it up, an unsubstantiated narrative that somehow also involves Israel and Tucker Carlson).
—
Elaine Godfrey,
The Atlantic,
9 June 2026
Chang’s unsubstantiated speculation that Doremus might have been texting coworkers on her way to work was insufficient.
—
Dan Eaton,
San Diego Union-Tribune,
18 May 2026
Its meetings at times became chaotic venues for casting doubt and airing unsubstantiated claims, often unchallenged, on the safety and efficacy of vaccines.
—
Jesse L. Goodman,
STAT,
18 May 2026
Overwhelmingly, those cases stem from reports later found to be false or unsubstantiated.
—
James R Mason,
Hartford Courant,
12 May 2026
See All Example Sentences for unsubstantiated
Elaine Godfrey,
The Atlantic,
9 June 2026
Chang’s unsubstantiated speculation that Doremus might have been texting coworkers on her way to work was insufficient.
—
Dan Eaton,
San Diego Union-Tribune,
18 May 2026
Its meetings at times became chaotic venues for casting doubt and airing unsubstantiated claims, often unchallenged, on the safety and efficacy of vaccines.
—
Jesse L. Goodman,
STAT,
18 May 2026
Overwhelmingly, those cases stem from reports later found to be false or unsubstantiated.
—
James R Mason,
Hartford Courant,
12 May 2026
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
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If these requirements are not met, the search is unreasonable and therefore unlawful, and evidence obtained in that search cannot be used in court, barring a good-faith exception.
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Justices ruled that sweeping use of cellphone data requires a warrant, a decision applying the Fourth Amendment, which protects against unreasonable searches and seizures, to new technology.
Adjective
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For decades, African football has faced criticism and skepticism, often based on unfounded racial stereotypes.
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The early fears that Hamilton was an existential threat to the university seemed—so far, at least—unfounded.
Adjective
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Now, one population, transgender youth and collegians, are targeted for specific and baseless discrimination.
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On the evening of June 2, his baseless case was further undercut when Republican Steve Hilton won the second spot on November’s ballot for governor, up against Democrat Xavier Becerra.
Adjective
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Nseyo notes there are plenty of unsupported myths around what causes UTIs, so stick to these tips.
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He is no longer charged with the capital offense of murder through the use of a firearm after Garnett dismissed it in January, finding the top count was legally unsupported by the other charges.
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 3 Jul. 2026.
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