unsolved
word
Definition
Not yet explained, answered, or resolved. Typically used for mysteries, crimes, problems, or puzzles that remain without a solution.
Usage & Nuances
Strongly associated with crime and mystery — 'unsolved murder', 'unsolved case', 'unsolved mystery' are the most common collocations. Also used in math/science: 'unsolved problem'. Implies the matter is still open and people are still looking for answers.
Example Sentences
The case has remained unsolved for over twenty years.
basic
There are many unsolved mysteries in the world of science.
basic
The police closed the file, leaving the murder unsolved.
basic
What bothers me is not the answer — it's all the unsolved questions we never even thought to ask.
natural
The documentary digs into one of the most infamous unsolved crimes in American history.
natural
Some of math's greatest unsolved problems have stumped the brightest minds for centuries.
natural