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

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

The faults have now been fixed, bringing some relief to the state-owned ferry firm which since last week has been forced to pare back services as it faces an "unprecedented" shortage of ships.

From BBC

Related Words

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