- a street or passage closed at one end.；a route or course leading nowhere
noun: cul-de-sac, plural noun: culs-de-sac
- 1. a street or passage closed at one end.
- ▪ a route or course leading nowhere the pro-democracy forces found themselves in a political cul-de-sac
- ▪ a vessel, tube, or sac, e.g., the cecum, open at only one end.