"act of derailing or causing to leave the rails," 1850, from French déraillement, from dérailler "to go off the rails" (see derail).
Entries linking to derailment
derail v.
1850 (Dionysius Lardner, "Railway Economy"), in both transitive and intransitive senses, "cause to leave the rails or run off the tracks; to run off the rails or tracks," from French dérailler "to go off the rails," from de- (see de-) + railler (see rail (n.1)). Related: Derailed; derailing.