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.
Those numbers are unheard-of today, Ms. López said. César Rodríguez, New York Times, 18 Jan. 2025 Its stars were on magazine covers (Rolling Stone included), and ratings stories in the Hollywood trades began taking the unusual step of noting how many people were recording episodes to watch or rewatch later — which was previously unheard-of behavior for all but the nerdiest of TV viewers. Alan Sepinwall, Rolling Stone, 16 Jan. 2025 The year demonstrated how global warming is loading the dice in favor of more destructive outcomes, from Hurricane Helene to a period during the summer when global average temperatures spiked to unheard-of levels. Andrew Freedman, Axios, 15 Jan. 2025 Finance, with its ability to ... Post Companies have adopted artificial intelligence with almost unheard-of speed, but there remains a significant gap between enthusiasm and results. Jason McDannold, Harvard Business Review, 19 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 2 Feb. 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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