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
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Two years later, a train derailed, and the air, water, and clay of East Palestine were poisoned. Mary Norris, New Yorker, 1 May 2026 His second year was derailed by injury. David Troy, FOXNews.com, 1 May 2026 Those plans were derailed after the war triggered a spike in jet fuel prices, upending Spirit's cost projections and complicating its exit from bankruptcy. David Shepardson, USA Today, 1 May 2026 Given all the things that can derail those winning combinations, that’s a lot of risk. Neil Greenberg, New York Times, 1 May 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 3 May. 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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