Definition of derail
1 : to cause to run off the rails
2 a : to obstruct the progress of : frustrate <security problems derailed the tour> b : to upset the stability or composure of <divorce … can seriously derail an employee — Joanne Gordon>
: to leave the rails
derailmentplay \-mənt\ noun
Examples of derail in a sentence
The train derailed in heavy snow.
The train was derailed by heavy snow.
Origin and Etymology of derail
French dérailler to throw off the track, from dé- de- + rail, from English
First Known Use: 1850
DERAIL Defined for English Language Learners
Definition of derail for English Language Learners
of a train : to leave its tracks
: to cause (a train) to leave its tracks
DERAIL Defined for Kids
Definition of derail for Students
1 : to leave or cause to leave the rails <The train derailed.>
2 : to make progress or success difficult for <Injuries derailed his plan for a championship.>
Seen and Heard
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