deplane (from) vs step off

deplane (from)

step off

verb
  • 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. 

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

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