derail

verb

de·​rail di-ˈrāl 

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

di-ˈrāl-mənt 

dē-

noun

Synonyms of derail

• distract
• disturb
• bother
• worry
• alarm
• concern
• unsettle
• agitate
• anger

Examples of derail in a Sentence

The train derailed in heavy snow.

The train was derailed by heavy snow.

Recent Examples on the Web

Police said officers, paramedics and firefighters were at the scene near Wickford train station in Essex, about 30 miles east of London (48 kilometers), after receiving reports that the rear carriages of a train derailed. — ABC News, 14 Aug. 2026

The news comes less than 24 hours after eighteen people were injured, including two seriously, after a passenger train derailed near Lewes in East Sussex, about 45 miles south of London. — Ivana Kottasová, CNN Money, 14 Aug. 2026

Yet, Bank of America's Michael Hartnett thinks surging national debt and higher bond yields could derail the strong run for equities. — Fred Imbert, CNBC, 14 Aug. 2026

Those possibilities are like what happened a little more than three years ago across the Ohio-Pennsylvania border in East Palestine, when a Norfolk Southern train derailed, bursting into flames and releasing toxic chemicals into the air. — Lauren Linder, CBS News, 13 Aug. 2026

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

Rhymes for derail

• airmail
• assail
• avail
• bewail
• blackmail
• cattail
• cocktail
• curtail
• detail
• dovetail
• email
• entail

Kids Definition

derail

verb

de·​rail di-ˈrā(ə)l 

: to cause to run off the rails

a train derailed by heavy snow

derailment

-mənt 

noun