UNHEARD-OF Synonyms: 32 Similar and Opposite Words

unheard-of

adjective

ˌən-ˈhərd-ˌəv

Definition of unheard-of

as in unprecedented

not known or experienced before houses selling at unheard-of prices

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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 That is unheard-of with prolonged exposure, cognitive processing, and certainly SSRIs, the current standard-of-care options. — Anderson Cooper, CBS News, 16 Aug. 2026 To fix the problems at the factory, the company would team up with yet another unheard-of partner promising technological innovation. — Jesse Coburn, ProPublica, 12 Aug. 2026 The darling of the screen charmed audiences around the globe, but had a tough time making love and romance work with her unheard-of level of stardom. — Angela Andaloro, PEOPLE, 12 Aug. 2026 The damage forced an almost unheard-of response from the grain trade itself. — Ingmar Rentzhog, Forbes.com, 1 Aug. 2026 See All Example Sentences for unheard-of

Recent Examples of Synonyms for unheard-of

Adjective

The movement has reached almost unprecedented proportions, with other sectors joining the students, demanding better learning conditions and fighting against the cost-of-living crisis, hike in fuel prices, and erosion of social welfare.

— Alessia Armenise, Condé Nast Traveler, 19 Oct. 2026
Moore’s Law has survived only on the basis of unprecedented international confederation.

— Gideon Lewis-Kraus, New Yorker, 19 Oct. 2026

Definition of unprecedented

Adjective

Massive novel diversity Resting up to 6,000 meters (19,700 feet) deep in the Pacific Ocean between Mexico and Hawaii, the Clarion-Clipperton Zone is strewn with millions of potato-sized metallic rocks.

— Mrigakshi Dixit, Interesting Engineering, 14 Oct. 2026
The critics already called the novel postcolonial and feminist.

— Literary Hub, Literary Hub, 14 Oct. 2026

Definition of novel

Adjective

An emergency program was followed by an initial slowdown in new cases after almost 20 million children received a vaccination in April and May.

— Arkansas Online, Arkansas Online, 18 Oct. 2026
In the middle of one of those summer heatwaves this year, Kember was in the promotional cycle for a record with his new partner of 15 years, Panda Bear.

— Gabriel Szatan, Pitchfork, 18 Oct. 2026

Definition of new

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unhealthy

unheard-of

unheated

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“Unheard-of.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/unheard-of. Accessed 22 Oct. 2026.

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Synonyms of unheard-of

adjective

Example Sentences

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