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derailment

American  
[dee-reyl-muhnt] / diˈreɪl mənt /

noun

  1. the act or process of derailing.

  2. Psychiatry. loosening of associations.


Etymology

Origin of derailment

1940–45; derail + -ment, or < French déraillement

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The immediate crisis is compounded by the derailment of future supply.

From The Wall Street Journal • Mar. 25, 2026

Stripping out certain one-time items, such as expenses related to its tie-up with Union Pacific and continued costs from its freight-train derailment in Ohio, earnings were $3.22 a share.

From The Wall Street Journal • Jan. 29, 2026

As officials called for patience, news broke of a second derailment in almost as many days.

From BBC • Jan. 21, 2026

"In the derailment and collision in Adamuz, Cordoba, there are injured people," the Andalusia region's emergency services posted on X.

From Barron's • Jan. 18, 2026

Chances are his train was late, because in 1984 there was a fire somewhere on the New York system every day and a derailment every other week.

From "The Tipping Point" by Malcolm Gladwell