preserve vs send off

preserve

verb
  • To save from decay by the use of some preservative substance, such as sugar or salt; to season and prepare (fruits, meat, etc.) for storage. 

  • To maintain throughout; to keep intact. 

  • To protect; to keep from harm or injury. 

noun
  • An activity with restricted access. 

  • A sweet spread made of any of a variety of fruits. 

  • A reservation, a nature preserve. 

send off

noun
  • farewell party 

  • funeral or memorial service 

verb
  • To show someone a red card, and dismiss them from the playing area. 

  • To provide a celebration for someone who is leaving; give a sendoff. 

  • To send; to dispatch. 

  • To emit; to emanate. 

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