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unheard–of

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adjective un·heard–of \-ˌəv, -ˌäv\

Simple Definition of unheard–of

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of unheard–of

  1. :  previously unknown; especially :  unprecedented <moving at unheard–of speeds>

1592

First Known Use of unheard–of

1592


UNHEARD–OF Defined for Kids

unheard–of

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

Definition of unheard–of for Students

  1. :  not known before <an unheard-of invention>




Learn More about unheard–of

  1. Spanish Central: Translation of unheard–of


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