wrong-way sign
nounUK /ˌrɒŋ ˈweɪ saɪn/
US /ˌrɔːŋ ˈweɪ saɪn/
A sign that tells you not to go that way.
The driver saw the wrong-way sign and turned around.
OTHER MEANINGS
2. A sign warning that traffic is coming toward you in the wrong direction.
A wrong-way sign flashed on the highway to warn drivers.
3. A notice placed to stop people from entering a restricted area.
A wrong-way sign blocked the entrance to the construction site.
4. A symbol showing that a path or lane is not for travel in that direction.
The wrong-way sign on the bike path kept riders safe.