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Synonyms

unprecedented

American  
[uhn-pres-i-den-tid] / ʌnˈprɛs ɪˌdɛn tɪd /

adjective

  1. without previous instance; never before known or experienced; unexampled or unparalleled.

    an unprecedented event.

    Synonyms:
    novel, exceptional, extraordinary, unique

unprecedented British  
/ ʌnˈprɛsɪˌdɛntɪd /

adjective

  1. having no precedent; unparalleled

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • unprecedentedly adverb
  • unprecedentedness noun

Etymology

Origin of unprecedented

First recorded in 1615–25; un- 1 + precedent + -ed 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But East Lothian Council's decision to install parking meters has been met with an "unprecedented" level of hostility.

From BBC

Dubai airport, the world's busiest for international traffic, and Jebel Ali seaport also suffered damage as the unprecedented attacks hit some of the city's major landmarks and revenue-earners.

From Barron's

Closing the Strait of Hormuz would be both unprecedented and difficult for Iran to pull off, analysts said.

From The Wall Street Journal

A new study published in Science offers an unprecedented look at that process.

From Science Daily

In an unprecedented move, on Dec. 2, 2025, the AEA announced that it had placed a lifetime ban on Summers from all its conferences and other activities.

From Salon