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Synonyms

unsubstantiated

American  
[uhn-suhb-stan-shee-ey-tid] / ˌʌn səbˈstæn ʃiˌeɪ tɪd /

adjective

  1. not substantiated; unproved or unverified.

    unsubstantiated allegations.

  2. being without form or substance.

unsubstantiated British  
/ ˌʌnsəbˈstænʃɪˌeɪtɪd /

adjective

  1. not established as valid or genuine

    unsubstantiated allegations
"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of unsubstantiated

First recorded in 1765–75; un- 1 + substantiate + -ed 2

Vocabulary lists containing unsubstantiated

Reading: Informational - High School

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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.

"Unsubstantiated", "highly defamatory", and a "fishing expedition", the company says of the potential evidence.

From BBC • Mar. 31, 2023

Unsubstantiated rumors and outright falsehoods spread widely in immigrant communities ahead of the presidential election in 2020.

From New York Times • Oct. 12, 2022

Unsubstantiated conspiracy theories have run rampant in the week following Epstein's death, and speculation has often filled in for fact while the public awaits the official results of Epstein's autopsy.

From Fox News • Aug. 15, 2019

Unsubstantiated claims that vaccines like MMR were associated with autism, multiple sclerosis, Crohn’s disease, etc., etc., and ill-informed celebrities have wreaked havoc with vaccination programs.

From Washington Post • Feb. 15, 2019

Unsubstantiated and bungled raids on young hackers and their families turned law enforcement into the Keystone Cops of cyberspace and the US Justice Department into a sworn enemy of the shareware community's most valuable members.

From Open Source Democracy by Rushkoff, Douglas

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.