0 a line of vehicles that have stopped or are moving only very slowly, because of an accident or other problem on the road in front of them -- （路上因受阻而形成的）车辆长队，长龙
Poorly upgraded roads and the formation of tailbacks also increase the potential danger.
When checked there were no tailbacks and so warning lights on the motorway were not switched on.
Tailbacks do not just happen—they take a while to build up.
When we arrived, a tailback of traffic over a mile long had already formed.
As for the first junction, there is already a considerable problem with traffic tailback at the expressway, particularly in the evening rush hour.
Some sections of the route are so narrow that one tractor might cause tailbacks for miles in the morning.
Tailbacks—far from getting better—would be almost certain to get worse.
I do not believe that removing payment for the crossing is any answer to the tailbacks or the problems with which we must cope.
