unheard-of

adjective

ˌən-ˈhərd-ˌəv How to pronounce unheard-of (audio)
Definition of unheard-ofnext
as in unprecedented
not known or experienced before houses selling at unheard-of prices

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of unheard-of The phenomenon reflects the recent evolution of the venture capital industry, the emergence of two extraordinary companies that have raised unheard-of sums of money, and the wide-open competition among them and others in AI. — Paresh Dave, Wired News, 5 June 2026 This spring, at the end of our 58th season, 60 Minutes grew rapidly with an unheard-of 9% jump in viewers on CBS. — Joanna Ossinger,laya Neelakandan, CNBC, 3 June 2026 This effort ultimately translated to a virtually unheard-of customer acquisition cost of less than one-half of one cent per new user. — Encyclopedia Britannica, 15 May 2026 The world has so many moving parts that extraordinary and even unheard-of things happen all the time. — Faye Flam, Scientific American, 7 May 2026 See All Example Sentences for unheard-of
Recent Examples of Synonyms for unheard-of
  1. unprecedented
  2. novel
  3. strange
  4. unfamiliar
  5. new
Adjective
  • The site will probe the internal structure of protons, neutrons and atomic nuclei with unprecedented precision.
    — Georgina Jedikovska, Interesting Engineering, 12 Aug. 2026
  • With ocean temperatures rising at unprecedented rates, warmer northern coastal waters may be enabling the rays to arrive in these waters earlier and to stay longer.
    — Sanidhya Sharma, Scientific American, 12 Aug. 2026
Definition of unprecedented
Adjective
  • The novel delves into the war experience of Palestinian women.
    — Literary Hub, Literary Hub, 14 Aug. 2026
  • Researchers in South Korea have recently developed a novel 3D printing method that allows soft actuators made from a single material to stretch or contract when exposed to heat.
    — Georgina Jedikovska, Interesting Engineering, 12 Aug. 2026
Definition of novel
Adjective
  • Investigators later ruled out trains and power lines as possible causes — and traced the fire’s point of origin to the same spot Child witnessed the man’s strange behavior.
    — Cindy Von Quednow, CNN Money, 10 Aug. 2026
  • And Dad actually makes an uncredited vocal cameo on one of the album’s more blessedly strange tracks.
    — Chris Willman, Variety, 9 Aug. 2026
Definition of strange
Adjective
  • People interested in donating should visit the organizations' official websites directly rather than relying on donation links circulating through unfamiliar social media accounts or messages.
    — Zachary Bynum, CBS News, 12 Aug. 2026
  • But a cleaner screen isn’t necessarily a more usable one if customers have to hunt for important functions, decipher unfamiliar icons or struggle to understand what the product is doing.
    — Expert Panel®, Forbes.com, 12 Aug. 2026
Definition of unfamiliar
Adjective
  • Balancing privacy and publicity isn’t new, says Alice Marshall, who runs her own public relations agency handling luxury travel clients.
    — Doug Gollan, Forbes.com, 11 Aug. 2026
  • After years of slow progress, a new development in in a Colorado town is finally close to getting the green light.
    — Olivia Young, CBS News, 11 Aug. 2026
Definition of new

Browse Nearby Words

unhealthy
unheard-of
unheated
See all Nearby Words

Cite this Entry

“Unheard-of.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unheard-of. Accessed 16 Aug. 2026.

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More from Merriam-Webster on unheard-of

Nglish: Translation of unheard-of for Spanish Speakers

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