What does "derail" mean?

Synonym of derailer: A device placed on railway tracks in order to cause a train to derail.

What is a synonym for "derail"?

Common synonyms include: derailer, dissuade, jump, unrail, unrail.

Pronounced //ˌdəˈɹeɪ.əl//.

//ˌdəˈɹeɪ.əl// noun, verb

noun, verb ·Uncommon ·Advanced level

Noun

1
Synonym of derailer: A device placed on railway tracks in order to cause a train to derail.
"The derail was placed deliberately so that the train would fall into the river."
2
An instance of diverting a conversation or debate from its original topic.

Verb

1
To cause to come off the tracks. transitive
"The train was destroyed when it was derailed by the collision."
2
run off or leave the rails wordnet
3
To come off the tracks. intransitive
"Fortunately, the CrossCountry train did not derail when it struck the mud. It could easily have been much worse."
4
cause to run off the tracks wordnet
5
To deviate from the previous course or direction. figuratively, intransitive
"The conversation derailed once James brought up politics."

Show 1 more definition

6
To cause to deviate from a set course or direction. figuratively, transitive
"The protesting students derailed the professor's lecture."

"The derail was placed deliberately so that the train would fall into the river."

From French dérailler (“to go off the rails”). Analyzable as de- + rail.

Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.