# unthinkable

/ənˈθɪŋkəbəɫ/ (US) · /ʌnθˈɪŋkəbəl/ (UK) · CEFR B2 · Adjective

Source: https://englishreference.com/word/unthinkable
Updated: 2026-05-07

## Definition

impossible to imagine or accept because it is so shocking or unlikely. You use this when something is too extreme to even consider.

For teachers: impossible to imagine or consider as a possibility; often used to describe events or ideas that are socially, morally, or practically unacceptable.

## Examples

- A few years ago, a global lockdown seemed unthinkable.
- The loss of the company's main server would have been unthinkable before they implemented the new backup system.
- In the current political climate, a compromise that was once considered standard has become unthinkable to both parties, leading to a total stalemate in negotiations.

## Usage notes

- Often used predicatively after linking verbs like 'be', 'seem', or 'become'.

---

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.