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.
Quantum computing promises to solve problems by allowing previously unheard-of processing speeds and predictive analytics. Chuck Brooks, Forbes, 24 Dec. 2024 Post Post Share Save Buy Copies Print Companies have adopted artificial intelligence with almost unheard-of speed, but there remains a significant gap between enthusiasm and results. Jason McDannold, Pak, paula Walworth, Harvard Business Review, 19 Dec. 2024 Zoom in: Virtual parties, unheard-of before COVID, are a growing fixture of work life. Emily Peck, Axios, 14 Dec. 2024 Firefighters doused nearly 300 brush fires across the city in November, including an unheard-of 215 blazes in the first 14 days of the month. Joseph Wilkinson, New York Daily News, 5 Dec. 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 30 Dec. 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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