D defs.my
Entry 1 sense Webster, 1913

Derail

/dĭr-āl'/ · De·rail · IPA /ˌdəˈɹeɪ.əl/
01 v. t. To cause to run off from the rails of a railroad, as a locomotive.
imp. & p. p. Derailed; p. pr. & vb. n. Derailing
  1. 1.
    To cause to run off from the rails of a railroad, as a locomotive.