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

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unprecedented British  

/ ʌnˈprɛsɪˌdɛntɪd /

adjective

1. having no precedent; unparalleled

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Other Word Forms

• unprecedentedly adverb
• unprecedentedness noun

Etymology

Origin of unprecedented

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

Example Sentences

"This ancient immigrant gives us an unprecedented look at conditions in the early universe," said Ji.

From Science Daily • Apr. 4, 2026

That is high for an aerospace and defense company, but not unprecedented.

From Barron's • Apr. 3, 2026

The request was unprecedented: It demanded not only publicly available voter data, such as names and addresses, but also sensitive information, including driver’s license and Social Security numbers.

From Salon • Apr. 3, 2026

“His talent and knowledge will be important additions to our ballclub, and we are happy to offer him this opportunity to showcase his talents to MLB clubs while giving fans unprecedented access to Ducks baseball.”

From Los Angeles Times • Apr. 2, 2026

But he found himself with an unprecedented problem.

From "An Abundance of Katherines" by John Green

Related Words

• bizarre
• extraordinary
• fantastic
• miraculous
• new
• remarkable
• singular
• uncommon
• unheard-of
• unique
• unparalleled
• unrivaled
• unusual