unsubstantiated

[ uhn-suh b-stan-shee-ey-tid ]

/ ˌʌn səbˈstæn ʃiˌeɪ tɪd /

not substantiated; unproved or unverified: unsubstantiated allegations.

being without form or substance.

Origin of unsubstantiated

First recorded in 1765–75; un-¹ + substantiate + -ed²

One commenter wrote that this unsubstantiated rumor clearly meant that “Rihanna had what was coming to her.”

Why We're So Hard on Janay Rice and Celebrity Survivors of Abuse |Amy Zimmerman |September 15, 2014 |DAILY BEAST
This in no way changes the fact that Bryan Singer is innocent of these unsubstantiated lies.

Bryan Singer Agreed to Settle Sex Abuse Lawsuit for $100,000, but Insists He’s Innocent |Tim Teeman |July 29, 2014 |DAILY BEAST
This is just the latest example of contradictory and unsubstantiated information from unnamed sources leaking from Kuala Lumpur.

Who Gagged the Search for MH370? |Clive Irving |June 22, 2014 |DAILY BEAST
“Whispers” in this case, means “unsubstantiated and probably made up rumors.”

Solange Is Blue Ivy’s Mom and Other Crazy Conspiracy Theories |Kevin Fallon |May 15, 2014 |DAILY BEAST

An unsubstantiated survey reports that 15.1 million of them are still shocked that Jeff Daniels won.

Emmy Awards Score Ratings High, Jon Hamm May Undergo Surgery |Culture Team |September 23, 2013 |DAILY BEAST
He conscientiously avoids the vague, the doubtful, the unsubstantiated.

Appletons' Popular Science Monthly, May, 1900 |Various
Criticism and comment on well-known and admitted facts are very different things from the assertion of unsubstantiated facts.

A Public Appeal for Redress to the Corporation and Overseers of Harvard University |Francis Ellingwood Abbot
The referee challenges the therapeutic claims on the basis that they are extravagant and unsubstantiated.

The Propaganda for Reform in Proprietary Medicines, Vol. 1 of 2 |Various
Then follows the unsubstantiated story which has done duty for Shakspeare and many other poets.

Robert Burns |Gabriel Setoun
He failed to winnow the sound historical material from that which was unsubstantiated or improbable.

The Northmen, Columbus and Cabot, 985-1503 |Various

unsubstantiated

/ (ˌʌnsəbˈstænʃɪˌeɪtɪd) /

not established as valid or genuine unsubstantiated allegations