unprecedented

unprecedented — adjective

1. describing an event, achievement, or situation that is the first of its kind, wi

1.adjectiveC2
Definition

describing an event, achievement, or situation that is the first of its kind, with no earlier example to compare it to

Example

Asher's promotion to manager at age twenty-two was unprecedented in the company's history.

unprecedented in [context]

The damage from the flood was unprecedented, leaving thousands of families homeless.

collocation: unprecedented damage / scale

Common collocations
  • unprecedented scale
  • unprecedented level
  • unprecedented challenge
  • unprecedented decision
  • unprecedented step
  • unprecedented rise
  • unprecedented growth
Synonyms
  • unparalleled

    stronger emphasis on being unmatched, often used in praise

  • unheard-of

    more informal; suggests something shocking or surprising

  • groundbreaking

    focuses on innovation and progress, usually positive

  • record-breaking

    specifically about measurable achievements or numbers

Antonyms

Grammar Patterns

unprecedented + noun

be + unprecedented

Usage Note

Commonly used in formal and journalistic writing. Frequently modifies nouns such as scale, level, decision, challenge, event, step, or rise. Often followed by 'in' to specify the domain (e.g. unprecedented in modern times).

Common Mistakes

This is an unprecedented record.
This is an unprecedented achievement.
'unprecedented record' is redundant, since a record is by definition something unprecedented.

Word family

Synonym discussion

Sense: adjective/1

All four words describe something unusual or remarkable, but they differ in tone and use. Unparalleled is the closest in formality to unprecedented and stresses that nothing else can match it — an unparalleled victory suggests a level no competitor has reached. Unheard-of is more informal and conversational, often with a hint of shock: an unheard-of delay implies something so rare that people are surprised by it. Groundbreaking focuses on innovation and progress, almost always positive — a groundbreaking study changes how people think about a topic. Record-breaking applies specifically to measurable achievements such as speed, size, or sales figures. For example, you might say a company saw an unprecedented level of growth (no prior example), but you would call the growth record-breaking only if it beat a specific numerical record.

unparalleled ↗unheard-ofgroundbreaking ↗record-breaking

Common collocations

Nouns

Adverbs

  • truly unprecedented
  • almost unprecedented
  • nearly unprecedented

Phrases

  • unprecedented level of
  • unprecedented scale of

Prepositions

  • unprecedented in

Etymology

LatinFrenchEnglish

Unprecedented comes from the prefix un- ('not') added to the adjective precedented, which itself comes from the noun precedent ('an earlier example'). The root goes back to Latin praecedere — prae- meaning 'before' and cedere meaning 'to go' — so literally 'not having gone before'. The word entered English in the early 1600s.