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 latest comments, however, threaten to derail progress on trade talks and other matters. — Siladitya Ray, Forbes.com, 17 July 2026

The analysts wrote that a common fear among investors is that the scale of infrastructure investment required for electrification becomes too expensive, derailing the sector’s growth. — Joseph Wilkins, CNBC, 17 July 2026

And Johnson’s gambit to attach the SAVE America Act to important legislation risks not only derailing bipartisan policy but another government shutdown, too. — Sorelle Wyckoff Gaynor, The Conversation, 17 July 2026

Even further back, another two-year deal to setup man Mike Adams was derailed by a significant shoulder injury. — Matt Gelb, New York Times, 16 July 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