# unsolved

/ənˈsɑɫvd/ (US) · /ʌnsˈɒlvd/ (UK) · CEFR B2 · Adjective

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

## Definition

describing a mystery, crime, or problem that has not been explained or fixed yet.

For teachers: referring to a problem, mystery, or crime for which no solution or explanation has been found. Often used to describe cold cases or mathematical paradoxes.

## Examples

- The mystery of the missing keys remains unsolved.
- Police are still looking for new evidence in the unsolved robbery that took place last winter.
- Despite decades of rigorous investigation and the application of modern forensic technology, the identity of the culprit in the 1974 case remains one of the city's most famous unsolved mysteries.

## Usage notes

- Typically used attributively before a noun or predicatively after a linking verb like 'remain' or 'stay'.

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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.