Definition of derailleur
: a mechanism for shifting gears on a bicycle that operates by moving the chain from one set of exposed gears to another
Recent Examples of derailleur from the Web
Though materials and build play a part in the Ajax’s silent operation, the main reasons are the 8-speed internal hub and belt drive at the heart of the bike’s derailleur-free drivetrain.
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Origin and Etymology of derailleur
French dérailleur, from dérailler
First Known Use: 1930
DERAILLEUR Defined for English Language Learners
Definition of derailleur for English Language Learners
: a part on a bicycle that is used to change gears by moving the chain from one gear to another one
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