derail

verb

de·​rail di-ˈrāl How to pronounce derail (audio)
dē-
derailed; derailing; derails
Synonyms of derailnext

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 How to pronounce derail (audio)
dē-
noun

Synonyms of derail

Relevance
See All Synonyms & Antonyms in Thesaurus

Examples of derail in a Sentence

The train derailed in heavy snow. The train was derailed by heavy snow.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
But such challenges are inevitable when dealing with complex vessels and should not derail necessary investments. — Holmes Liao, Foreign Affairs, 4 Sep. 2026 The latest efforts to derail El-Sayed’s campaign include weaponizing his association with leftist Twitch streamer Hasan Piker. — Lorraine Ali, Los Angeles Times, 3 Sep. 2026 The Phillies could explore some type of bullpen role for Painter in the postseason, although his first-inning troubles and lack of experience as a reliever might be enough to derail that idea. — Matt Gelb, New York Times, 3 Sep. 2026 Not everyone is worried yields will derail the bull market, however. — Fred Imbert, CNBC, 1 Sep. 2026 See All Example Sentences for derail

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

Time Traveler
The first known use of derail was in 1850

Rhymes for derail

See All Rhymes for derail

Browse Nearby Words

deraign
derail
derailleur
See all Nearby Words

Cite this Entry

“Derail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/derail. Accessed 7 Sep. 2026.

Copy Citation

Kids Definition

derail

verb
de·​rail di-ˈrā(ə)l How to pronounce derail (audio)
: to cause to run off the rails
a train derailed by heavy snow
derailment
-mənt How to pronounce derail (audio)
noun
Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster

Word of the Day

Listen to the pronunciation of gist

See Definitions and Examples »

Popular in Grammar & Usage

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

A List of Most Commonly Confused Words

Why do we use apostrophes to show possession?

Is it 'nerve-racking' or 'nerve-wracking'?

What's the difference between 'fascism' and 'socialism'?
See More

Popular in Wordplay

See More

The Longest Long Words List

Stay Woke

Ye Olde Nincompoop: Old-Fashioned Words for 'Stupid'

14 Phobias You Probably Haven't Heard Of

The Words of the Week - Sept. 4
See More

Popular

See More

A Who’s Who Regarding ‘Who’s’ and ‘Whose’

The Longest Long Words List

Stay Woke
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
The Missing Letter A daily crossword with a twist
anagrams on a chalk board
Word Builder Quiz Vol. 2 Pick the letter that when added to a word will ma...
See All