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unheard-of

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adjective un·heard-of \ ˌən-ˈhərd-ˌəv , -ˌäv \

Definition of unheard-of

:previously unknown; especially :unprecedented

moving at unheard-of speeds

See unheard-of defined for English-language learners

See unheard-of defined for kids

First Known Use of unheard-of

1592

unheard-of Synonyms

Synonyms

fresh, novel, original, strange, unaccustomed, unfamiliar, unheard-of, unknown, unprecedented

Antonyms

familiar, hackneyed, old, time-honored, tired, warmed-over

Related Words

innovative, unique; nontraditional, unconventional, untried, unused, unworn; pathbreaking, pioneering, trailblazing

Near Antonyms

conventional, established, traditional, tried, tried-and-true; derivative, imitative

UNHEARD-OF Defined for English Language Learners

unheard-of

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adjective

Definition of unheard-of for English Language Learners

: not known to have existed or happened before : very unusual

UNHEARD-OF Defined for Kids

unheard-of

adjective un·heard-of \ ˌən-ˈhərd-ˌəv , -ˌäv \

Definition of unheard-of for Students

:not known before an unheard-of invention

Learn More about unheard-of

See words that rhyme with unheard-of Thesaurus: All synonyms and antonyms for unheard-of Nglish: Translation of unheard-of for Spanish speakers

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WORD OF THE DAY

toothsome

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agreeable, attractive, or delicious

BROWSE DICTIONARY

unhealthy

unheard

unheard-of

unhearing

unheartsome

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