derailleur

[dih-rey-ler]

noun

1. a gear-shifting mechanism on a bicycle that shifts the drive chain from one sprocket wheel to another.

derailleur

/ dəˈreɪljə /

noun

1. a mechanism for changing gear on bicycles, consisting of a device that lifts the driving chain from one sprocket wheel to another of different size

Word History and Origins

Origin of derailleur¹

1945–50; < French dérailleur literally, a device causing disengagement or derailing, equivalent to déraill ( er ) to derail + -eur -eur

Word History and Origins

Origin of derailleur¹

French dérailleur derailer

Example Sentences

A single derailleur cable found snapped in two during a bike ride I took in Italy morphed into something more sinister.

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The ’70s also saw an explosion in bike sales, both as a result of high gas prices and the introduction of the 10-speed derailleur.

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Using the updated Google Lens to identify a bike’s derailleur.

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These designs often require absurdly long chains slung between the pedals and rear derailleur.

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The recumbent trikes have been waiting for months for rear derailleurs, a small but crucial part that is built in Taiwan.

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