derailleur

noun

de·​rail·​leur di-ˈrā-lər 

: a mechanism for shifting gears on a bicycle that operates by moving the chain from one set of exposed gears to another

Examples of derailleur in a Sentence

Recent Examples on the Web

View 6 Images Many ebikes sport a derailleur hanging out back to giver riders more flexibility than single-speeders. —Paul Ridden, New Atlas, 18 Feb. 2025

Priority Bikes have a niche corner of the market with their low-maintenance internal belt drive, which replaces the chain and standard derailleur with an internal hub system. —Maggie Slepian, Travel + Leisure, 11 Feb. 2025

This also meant upgrading the shifter and rear derailleur and lengthening the chain. —Emily Lapointe, Outside Online, 5 Feb. 2025

But after trying out ideas with simplified internal gear hubs and derailleurs, SRAM recommended the two-chain design and donated it to the bike charity. —Kevin Purdy, Ars Technica, 4 Feb. 2025

Word History

Etymology

French dérailleur, from dérailler

First Known Use

1930, in the meaning defined above

Rhymes for derailleur

• blackmailer
• inhaler
• retailer
• wholesaler
• bailer
• bailor
• baler
• jailer
• jailor
• paler
• sailer
• sailor

Kids Definition

derailleur

noun

de·​rail·​leur di-ˈrā-lər 

: a device for shifting gears on a bicycle that operates by moving the chain from one set of exposed gears to another

Etymology

from French dérailleur "gear changing device," from dérailler "to derail"