blind alley
idiomPart ofalley
blind alley — idiom
1. a way of trying to solve a problem or reach a goal that leads nowhere and forces
1.idiom
Definition
a way of trying to solve a problem or reach a goal that leads nowhere and forces you to start again.
Example
After three weeks of testing, the engineers realised the new design was a blind alley.
Detective Park spent two months chasing the ex-husband, but the lead turned out to be a blind alley.