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derail

verb

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

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.
Charmast Portable Charger with Built-in Cables Travelers know that nothing derails a trip faster than a dead phone battery. Chaise Sanders, Travel + Leisure, 3 Dec. 2025 But in a comprehensive report given to city of San Diego officials just before Thanksgiving, MTS officials said looming deficits of more than $120 million per year could derail this progress with service cuts and fare hikes. David Garrick, San Diego Union-Tribune, 3 Dec. 2025 On the other, dealing with diarrhea or frequent trips to the bathroom can derail your work and interrupt your daily routines. Daryl Austin, USA Today, 1 Dec. 2025 On the platform, the woman shared how a casual restaurant visit with friends turned unexpectedly tense after a simple attempt to take a photo of her food derailed the evening. Tereza Shkurtaj, PEOPLE, 30 Nov. 2025 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 4 Dec. 2025.

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

Last Updated: - Updated example sentences
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