unheard-of

adjective

un·​heard-of ˌən-ˈhərd-ˌəv How to pronounce unheard-of (audio)
-ˌäv
Synonyms of unheard-ofnext
: previously unknown
especially : unprecedented
moving at unheard-of speeds

Examples of unheard-of in a Sentence

houses selling at unheard-of prices
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
While investors may balk at the thought of holding bonds from fiscal basket cases like Chicago or the state of Illinois, Jones says actual defaults are almost unheard-of, since government entities don’t go out of business. Jeff John Roberts, Fortune, 29 Jan. 2026 Capital spend is at an unheard-of level. Tim Bajarin, Forbes.com, 5 Jan. 2026 Revenue-sharing is not unheard-of in modern college coaching contracts, but Sportico is unaware of any other deal that has donation-sharing. Scott Soshnick, Sportico.com, 18 Dec. 2025 Then, in an almost unheard-of reversal, Trump renominated Isaacman last week. Burgess Everett, semafor.com, 13 Nov. 2025 See All Example Sentences for unheard-of

Word History

First Known Use

1592, in the meaning defined above

Time Traveler
The first known use of unheard-of was in 1592

Browse Nearby Words

Cite this Entry

“Unheard-of.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unheard-of. Accessed 10 Feb. 2026.

Kids Definition

unheard-of

adjective
un·​heard-of
-ˌəv
-ˌäv
: previously unknown : unprecedented
moving at unheard-of speeds

More from Merriam-Webster on unheard-of

Last Updated: - Updated example sentences
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