unheard-of

• unheard of

unheard-of (comparative more unheard-of, superlative most unheard-of)

1. Previously unknown; unprecedented.
   • 1912 January, Zane Grey, chapter 9, in Riders of the Purple Sage […], New York, N.Y.; London: Harper & Brothers Publishers, →OCLC:

     Starvation in the uplands was not an unheard-of thing […]

   • 2004, Peter Bondanella, chapter 4, in Hollywood Italians: Dagos, Palookas, Romeos, Wise Guys, and Sopranos, page 175:

     Prohibition produced the immense and previously unheard-of wealth that launched truly organized crime in America.

2. Unknown or known to only few people.