ditch vs jettison

ditch

verb
  • To discard or abandon. 

  • To dig ditches around. 

  • To dig ditches. 

  • To throw into a ditch. 

  • To deliberately not attend classes; to play hookey. 

  • To deliberately crash-land an airplane on water. 

noun
  • A trench; a long, shallow indentation, as for irrigation or drainage. 

  • A raised bank of earth and the hedgerow on top. 

jettison

verb
  • To let go or get rid of as being useless or defective. 

  • To eject from a boat, submarine, aircraft, spaceship or hot-air balloon, so as to lighten the load. 

noun
  • Items that have been or are about to be ejected from a boat or balloon. 

  • The action of jettisoning items. 

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