jettison vs offload

jettison

noun
  • The action of jettisoning items. 

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

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

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

offload

noun
  • The act of offloading something, or diverting it elsewhere. 

  • The act of passing the ball to a team mate when tackled. 

verb
  • to deny a person on a standby list due to lack of space. 

  • to unload. 

  • to get rid of things, work, or problems by passing them on to someone or something else. 

  • to change a passengers' ticket status from "checked in" to "open", allowing further changes. (This applies regardless of whether the passenger has boarded the aircraft or not). 

  • to pass the ball. 

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