derail

verb

de·​rail di-ˈrāl How to pronounce derail (audio)
dē-
derailed; derailing; derails
Synonyms of derailnext

transitive verb

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

intransitive verb

: to leave the rails
derailment noun

Examples of derail in a Sentence

The train derailed in heavy snow. The train was derailed by heavy snow.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The train did not derail as a result of the incident, Partida confirmed, but a fuel spill occurred. Joe Kottke, NBC news, 17 Mar. 2026 But Lowe never got on the field last year, as his freshman year was derailed by injury. Adam Lichtenstein, Sun Sentinel, 17 Mar. 2026 Earlier this season, SMU was projected to be as high as a six or seven seed before an injury to starting guard BJ Edwards derailed the Mustangs’ last three weeks of the season. Lia Assimakopoulos, Dallas Morning News, 15 Mar. 2026 After the brief interruption, Green shook off the incident and finished the set, unwilling to let one audience member derail the night. Jessica Lynch, Billboard, 15 Mar. 2026 See All Example Sentences for derail

Word History

Etymology

French dérailler to throw off the track, from dé- de- + rail, from English

First Known Use

1850, in the meaning defined at transitive sense 1

Time Traveler
The first known use of derail was in 1850

Browse Nearby Words

Cite this Entry

“Derail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/derail. Accessed 18 Mar. 2026.

Kids Definition

derail

verb
de·​rail di-ˈrā(ə)l How to pronounce derail (audio)
: to cause to run off the rails
a train derailed by heavy snow
derailment noun

More from Merriam-Webster on derail

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