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.
Industry observers said the Endangered Species Act exemption could have significant implications for energy companies by streamlining approvals of new projects and impeding opponents’ ability to derail drilling plans. Matthew Brown, Los Angeles Times, 31 Mar. 2026 Indianapolis began 8-2 before a litany of injuries, most notably quarterback Daniel Jones’ ruptured right Achilles tendon, derailed its promising campaign. James Boyd, New York Times, 30 Mar. 2026 However, a series of injuries, poor coaching, and the career revival of Daniel Jones derailed any momentum Richardson had gained. Michael Gallagher, MSNBC Newsweek, 30 Mar. 2026 Coach Erik Spoelstra in recent days has insisted that the Heat only can be the best version of themselves with Powell and Herro thriving as starters, stressing a commitment to such an approach, one now again derailed at least for another night. Ira Winderman, Sun Sentinel, 29 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 2 Apr. 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

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