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

The Stanley Cup will have a new home this year after the back-to-back champion Florida Panthers had their season derailed by injuries. —Stephen Whyno, Chicago Tribune, 14 Apr. 2026

The most recent concerns stemmed from the Iran war, where investors feared a spike in oil prices and inflation would push interest rates sharply higher and derail the rally. —Alexa Lomonaco, CNBC, 14 Apr. 2026

Swalwell personally addressed those claims at a campaign stop in Sacramento last Tuesday, saying the accusations were false and suggesting they were intended to derail momentum in his campaign for governor. —William Melhado, Sacbee.com, 13 Apr. 2026

In high-cost cities, the building of new homes and apartment complexes is often derailed in local planning and zoning-board meetings. —Idrees Kahloon, The Atlantic, 13 Apr. 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