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 initial push to revive the series was derailed in part by the allegations against the original show’s creator, Bill Cosby. — Los Angeles Times, 28 Sep. 2026

The nor’easter derailed my plans for an outdoor run over the weekend. — Alex Harring, CNBC, 28 Sep. 2026

The 43-year-old right-hander was making his second start of the year and first since March 30 in a season derailed by a sore hip and hamstring injury. — Arkansas Online, 27 Sep. 2026

But consecutive holding penalties on Cody Mauch and Graham Barton derailed the drive and McLaughlin kicked a 28-yard field goal to tie it. — CBS News, 27 Sep. 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