unheard-of

adjective

un·​heard-of ˌən-ˈhərd-ˌəv How to pronounce unheard-of (audio)
-ˌäv
: 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.
By using the concepts of quantum mechanics to execute operations at previously unheard-of speeds and efficiency, quantum computing is revolutionizing industries and changing the technological landscape. Rohan Pinto, Forbes, 20 Nov. 2024 Before the pandemic, Europeans working for U.S. companies weren’t unheard-of, but holding U.S.-based roles with American-level salaries was a rarity. Samuel Burke, Fortune Europe, 28 Oct. 2024 The directors and the CEO had reached an impasse over the latter’s plan to take the company private; still, resigning en masse is an unheard-of step for a startup board. Lila MacLellan, Fortune, 18 Oct. 2024 Hurricanes are particularly efficient at concentrating large quantities of water vapor and wringing it out at nearly unheard-of rates, as seen in the deluges in the Tampa-St. Petersburg area during Milton and in western North Carolina during Helene. Andrew Freedman, Axios, 15 Oct. 2024 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

Dictionary Entries Near unheard-of

Cite this Entry

“Unheard-of.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unheard-of. Accessed 24 Nov. 2024.

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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