unheard–of

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

Definition of unheard–of

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

First Known Use of unheard–of

1592


UNHEARD–OF Defined for English Language Learners

unheard-of

play
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

play
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


Seen and Heard

What made you want to look up unheard–of? Please tell us where you read or heard it (including the quote, if possible).

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

WORD OF THE DAY

an incorrigible rascal

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

  • istock-refers-to-this-as-a-tumble-of-strawberries-which-sounded-pretty-nice-to-us
  • Which is a synonym of garner?
How Strong Is Your Vocabulary?

Test your vocabulary with our 10-question quiz!

TAKE THE QUIZ
Citation

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!