Definition from Wiktionary, the free dictionary
derail (plural derails)
- A device placed on railway tracks causing a train to derail.
- The derail was placed deliberately so that the train would fall into the river.
- (transitive) To cause to come off the tracks.
- The train was destroyed when it was derailed by the penny.
- (intransitive) To come off the tracks.
- (intransitive) To deviate from the previous course or direction.
- The conversation derailed once James brought up politics.
- (transitive) To cause to deviate from a set course or direction.
- The protesting students derailed the professor's lecture.
- For usage examples of this term, see Citations:derail.
to come off the tracks
to deviate from the previous course or direction
to cause to deviate from a set course or direction