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

Hence, the complaints from both Amazon and SpaceX might derail the F2 satellite. — Michael Kan, PC Magazine, 29 Aug. 2026

Madrigal will play Dan, James’ divorced best friend whose plans for single life are derailed by James and Jeanie’s impulsive wedding. — Rosy Cordero, Deadline, 28 Aug. 2026

Next year’s Superman follow-up Man of Tomorrow hopes to avoid whatever lingering DC baggage and other factors derailed Supergirl. — Mark Hughes, Forbes.com, 28 Aug. 2026

The progressive left is working hard to derail America’s AI dominance by blocking data center construction. — Staff, FOXNews.com, 28 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