derailer

plural derailers

1. One who, or that which, derails.
   1. rail transportSynonym of derail: A device placed on railway tracks in order to cause a train to derail.

      Synonyms: derail

2. alternativeuncommoncyclingAlternative spelling of derailleur.

   Inside, two bearded men are working on a busted fuel pump, and another is repairing a bicycle derailer.

   2016, Erik Reece, Utopia Drive: A Road Trip Through America’s Most Radical Idea, New York, N.Y.: Farrar, Straus and Giroux, →ISBN, page 170

   3 more examples

   Through sheer ingenuity and resourcefulness, these men handproduced parts such as derailers, stands, seat posts, cranks, fenders, and all manner of elements used in the production of a functional bicycle.

   2009, Christine Elliott, David Jablonka, “Cycles Alex Singer”, in Custom Bicycles: A Passionate Pursuit, Images Publishing, →ISBN, page 72, column 2

   Very few bicycles are of a different color or employ more gears with derailer sprockets and hand brakes. […] In short, most adult commuter bicycles are almost interchangeable; and therein likes the tale. […] At first glance, one wonders how commuters can identify their own machine from the pack of identical black bicycles, particularly if they are in the center of the pack. The answer is, they don't! They simply grab one that is convenient, ride it home, and then return it to the pack the next day.

   2009, Louis G. Perez, “Society in the Twenty-first Century”, in Frank W. Thackeray, John E. Findling, editors, The History of Japan (The Greenwood Histories of the Modern Nations), 2nd edition, Westport, Conn.; London: Greenwood Press, →ISBN, →ISSN, page 202

   Recent American attempts to further Anglicize the word to “derailer” have met with little success. In any case, no rails are involved.

   [2016, Tony Hadland, Hans-Erhard Lessing, Bicycle Design: An Illustrated History, MIT Press, →ISBN, page 246