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
Superstar Peter Sagan stayed upright, but his chain jammed into his front derailleur and needed servicing.
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.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'derailleur.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
Origin and Etymology of derailleur
French dérailleur, from dérailler
First Known Use: 1930See Words from the same year
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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