dismount vs step off

dismount

verb
  • To (cause to) get off (something). 

  • To come down; to descend. 

  • To throw (cannon) off their carriages. 

  • To make (a mounted drive) unavailable for use. 

noun
  • The part of a routine in which the gymnast detaches from an apparatus. 

step off

verb
  • Used other than figuratively or idiomatically: see step, off. 

  • To avoid a conflict; to back down 

  • To measure by steps or paces; hence, to divide (a space), or to form a series of marks, by successive measurements, as with dividers. 

How often have the words dismount and step off occurred in a corpus of books? (source: Google Ngram Viewer )