as in unreasonable
having no basis in reason or fact
an unsubstantiated claim that was thrown out of court
Synonyms & Similar Words
Relevance
Antonyms & Near Antonyms
Example Sentences
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Recent Examples of unsubstantiated
Trump promised during the 2024 presidential campaign to release the files in their entirety and Patel before taking the FBI job had pushed unsubstantiated claims about who was in them.
—
Luke Barr, ABC News, 16 Sep. 2025
Andrew Caballero-Reynolds / AFP via Getty Images Yet, that has not prevented people from calling for justice for Reed on social media and circulating unsubstantiated allegations regarding his death.
—Daniella Silva, NBC news, 16 Sep. 2025
Allowing the President to unlawfully remove Governor Cook on unsubstantiated and vague allegations would endanger the stability of our financial system and undermine the rule of law.
—Siladitya Ray, Forbes.com, 10 Sep. 2025
There were unsubstantiated reports of a gunman in the facility, and the ATF, in a joint operation with the New Orleans SWAT team, stormed the location with guns drawn to hunt down a gunman who never materialized.
—Mandi Wright, Freep.com, 31 Aug. 2025
See All Example Sentences for unsubstantiated
Luke Barr, ABC News, 16 Sep. 2025
Andrew Caballero-Reynolds / AFP via Getty Images Yet, that has not prevented people from calling for justice for Reed on social media and circulating unsubstantiated allegations regarding his death.
—Daniella Silva, NBC news, 16 Sep. 2025
Allowing the President to unlawfully remove Governor Cook on unsubstantiated and vague allegations would endanger the stability of our financial system and undermine the rule of law.
—Siladitya Ray, Forbes.com, 10 Sep. 2025
There were unsubstantiated reports of a gunman in the facility, and the ATF, in a joint operation with the New Orleans SWAT team, stormed the location with guns drawn to hunt down a gunman who never materialized.
—Mandi Wright, Freep.com, 31 Aug. 2025
See All Example Sentences for unsubstantiated
Recent Examples of Synonyms for unsubstantiated
Adjective
-
Many of our technologies are built on the not-unreasonable assumption that openness is good, and that more common knowledge is better.—
Joshua Rothman,
New Yorker,
14 Oct. 2025
-
Each side of the issue argues that the other is unreasonable and operating in bad faith.—
Taylor Seely,
AZCentral.com,
9 Oct. 2025
Adjective
-
Still, the Epstein saga might have gradually faded from the national consciousness, even in spite of the widespread, unfounded belief that his 2019 suicide in a jail cell while awaiting trial was in fact a murder carried out to prevent him from implicating associates in his crimes.—
Miles Klee,
Rolling Stone,
16 Oct. 2025
-
The bull’s sheer size and the location of the hunt spawned unfounded rumors that Brooks had committed game violations.—
Natalie Krebs,
Outdoor Life,
15 Oct. 2025
Adjective
-
More severe weather events due to global warming may be driving some of the baseless theories, scientists say.—
Stephanie Armour,
CNN Money,
16 Oct. 2025
-
The baseless claims against Dominion caused one of its executives to go into hiding in 2020, and led to numerous defamation lawsuits.—
NPR Washington Desk,
NPR,
9 Oct. 2025
Adjective
-
The claim that flu shots increase flu transmission is absurd and unsupported by evidence.—
Flavia Mangan Colgan,
San Diego Union-Tribune,
7 Oct. 2025
-
In November, O'Brady, 40, will embark on a solo, unsupported 2,000-mile ski crossing of Antarctica over 110 days.—
Bryan Alexander,
USA Today,
2 Oct. 2025
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unsubstantiated. Accessed 19 Oct. 2025.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
Share