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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.
Then, in an almost unheard-of reversal, Trump renominated Isaacman last week. Burgess Everett, semafor.com, 13 Nov. 2025 Milei’s agenda of deregulation and free markets was unheard-of in deeply statist Argentina. Agustina Vergara Cid, Oc Register, 25 Oct. 2025 For a candidate to alienate the most powerful individuals in their political party even before a race gets going seriously is an unheard-of no-no. Thomas Elias, Mercury News, 14 Oct. 2025 Coach Outlet’s Fall Favorites Event is bringing discounts of up to 70% off the house’s leather goods and ready-to-wear, which translates to some unheard-of prices. Jake Henry Smith, Glamour, 13 Oct. 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 5 Dec. 2025.

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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