# unprecedented

/ənˈpɹɛsɪˌdɛntɪd/ (US) · /ʌnpɹˈɛsɪdəntɪd/ (UK) · CEFR C1 · Adjective

Source: https://englishreference.com/word/unprecedented
Updated: 2026-05-02

## Definition

never done or known before. You use this to describe something that is completely new or happens on a scale that has never been seen in the past.

For teachers: having no previous example or parallel in history. Often used to describe the scale, speed, or nature of a significant event that lacks a historical equivalent.

## Examples

- The city is facing an unprecedented heatwave this summer.
- The government took the unprecedented step of closing all borders to prevent the spread of the new virus.
- The rapid integration of artificial intelligence into daily life represents an unprecedented shift in how humans interact with technology, challenging existing legal and ethical frameworks.

## Usage notes

- Typically used to modify nouns representing events, changes, or levels of growth.

---

From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.