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

Some of the tightest restrictions are in Iran and Israel, although Gulf monarchies, targets of unprecedented drone and missile attacks from Iran, have also imposed tighter controls.

From Barron's

But the Iran war has upended a number of assumptions, including how the stock market might react to an unprecedented series of events in energy markets.

From Barron's

Premier League clubs voted for the new financial rules in November, during an unprecedented campaign in Europe.

From BBC

“The scale of this release is unprecedented: the world has never had a release of oil reserves at this one million per day rate for this length of time,” Mr. Biden declared.

From The Wall Street Journal

“Due to this unprecedented volatility, the jet fuel price assumption underlying Air New Zealand’s 26 February 2026 guidance is no longer appropriate,” the company said.

From The Wall Street Journal

Related Words

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