0 If a train derails or is derailed, it comes off the railway tracks. --
1 to prevent a plan or process from succeeding: --
3 to stop something from succeeding: --
The last six coaches were completely derailed about 300 yards further on and one turned over on its side.
The third and fourth coaches were derailed and damaged.
The locomotive and the first two coaches of the passenger train were derailed, as were a number of the oil tank wagons.
Six months later a train was directed over the points and was derailed.
One coach of the standing train was derailed and the guard and six passengers were injured.
Such derails are not held centrally and could be obtained only at disproportionate cost.
The collison resulted in the rear coach becoming derailed and the locomotive damaged.
I hope we shall not be derailed in all this.
