unsubstantiated
adjective
un·sub·stan·ti·at·ed
ˌən-səb-ˈstan(t)-shē-ˌā-təd 
: not proven to be true : not substantiated
an unsubstantiated rumor/report
a plausible but unsubstantiated theory
Examples of unsubstantiated in a Sentence
an unsubstantiated claim that was thrown out of court
Recent Examples on the Web
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
Members of a key vaccine advisory committee suggested digging into concerns, and Kennedy has made unsubstantiated claims that the additive is linked to allergies and autism.
—Kayla Hayempour, NBC news, 26 Dec. 2025
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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
Members of a key vaccine advisory committee suggested digging into concerns, and Kennedy has made unsubstantiated claims that the additive is linked to allergies and autism.
—Kayla Hayempour, NBC news, 26 Dec. 2025
See All Example Sentences for unsubstantiated
Cite this Entry
“Unsubstantiated.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unsubstantiated. Accessed 28 Jan. 2026.
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