Home › Words › D › derailerderailer/dɪˈɹeɪlə/derailer means one who, or that which, derails.derailer is pronounced /dɪˈɹeɪlə/.EtymologyFrom derail + -er. Sense 2 is an Anglicization of French dérailleur. Doublet of derailleur.nounOne who, or that which, derails.One who, or that which, derails.; Synonym of derail: A device placed on railway tracks in order to cause a train to derail.Definitions & examples from Wiktionary (CC BY-SA 3.0).Words closest in meaningBy meaning, not spelling — each word's AI semantic fingerprint, nearest first.derailing 71% match — The act by which something is derailed. vs derailer →derailment 68% match — The action of a locomotive or train leaving the rails along which it runs. vs derailer →derailleur 68% match — A mechanism on a bicycle wheel used while cycling to move the bicycle chain from one sprocket (gear) to another, to change speeds. vs derailer →deranger 66% match — Someone or something that deranges. vs derailer →derail 66% match — Synonym of derailer: A device placed on railway tracks in order to cause a train to derail. vs derailer →sidetracker 63% match — One who sidetracks something. vs derailer →disarranger 63% match — One who disarranges. vs derailer →derogator 62% match — A detractor. vs derailer →