unsubstantiated
Americanadjective
-
not substantiated; unproved or unverified.
unsubstantiated allegations.
-
being without form or substance.
adjective
Etymology
Origin of unsubstantiated
First recorded in 1765–75; un- 1 + substantiate + -ed 2
Vocabulary lists containing unsubstantiated
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Romanian officials said they had confirmed it was a Russian drone but Moscow said "accusations" of its involvement were "unsubstantiated".
From BBC ● Jun. 5, 2026
“He looks forward to vindicating himself in court, where such matters are decided — and not in the media — based on admissible, material evidence, not rank speculation and unsubstantiated allegations.”
From Los Angeles Times ● Jun. 3, 2026
At the telecommunications company’s call for first-quarter results, management provided no clarity beyond its refusal to comment “on unsubstantiated reports,” the analysts say.
From The Wall Street Journal ● May 14, 2026
These claims were unsubstantiated as post-election polling shows that transgender policies are were often ranked low in priorities for surveyed voters.
From Salon ● Apr. 5, 2026
The critical issue is the quality of the purported evidence, rigorously and skeptically scrutinized—not what sounds plausible, not the unsubstantiated testimony of one or two self-professed eyewitnesses.
From "Cosmos" by Carl Sagan
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.