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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.

Brent could go as high as $200 a barrel, Haigh said, with a caveat: “I’m guessing at this point…This is unprecedented.”

From The Wall Street Journal

More recently, Iran saw an unprecedented crackdown by the Basij and other security forces on protests that swept across the country in December and January.

From BBC

In a statement issued by the firm announcing it had appointed administrators, it said the campaign had secured "unprecedented engagement" to help keep the business operating.

From BBC

New instruments are now capable of measuring the universe with unprecedented accuracy.

From Science Daily

Clare returned the book to its dusty hiding place, forced to face a most harrowing reality: This was unprecedented.

From Literature

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.