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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

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.

See Examples For:

Monroe’s personal legacy is like a charm bracelet hung with more unsubstantiated rumors than genuine facts, but one undeniable trait was her thirst to defy the world’s expectations.

From Salon Jul. 6, 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

Some Democrats had privately dismissed rumors of his playboy lifestyle as unsubstantiated, according to people familiar with the conversations.

From The Wall Street Journal Apr. 16, 2026

Iran-aligned group Harakat Ashab al-Yamin al-Islamiya - The Islamic Movement of the People of the Right Hand - made an unsubstantiated claim of responsibility for the attack on its Telegram channel.

From BBC Mar. 24, 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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