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.
Plus every radio station and local television channel is broadcasting an equally grateful ad, commemorating this previously unheralded, unheard-of cruncher of numbers? David Fear, Rolling Stone, 5 June 2025 The film is notable for a dodge ball scene that goes disgustingly awry, a long gay kiss — an unheard-of smooch in 1981 — between Andrew and a bully, and for Arngrim’s goth-twink fabulous costumes, including the silkiest cape. Erik Piepenburg, New York Times, 2 June 2025 With vacancy rates at an unheard-of 1.4% and rents going up and up and up, New York needs scads of new units. New York Daily News Editorial Board, New York Daily News, 1 June 2025 Google claims Gemini Diffusion is capable of previously unheard-of accuracy in complex math and coding. Ryan Whitwam, ArsTechnica, 20 May 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 Jun. 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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