incomer vs predecessor

incomer

noun
  • An outsider who moves to a community or a place; (used by those who consider themselves to be its original inhabitants). 

  • One who comes in. 

predecessor

noun
  • A model or type of machinery or device which precedes the current (or later) one. Usually used to describe an earlier, outdated model. 

  • One who precedes; one who has preceded another in any state, position, office, etc.; one whom another follows or comes after, in any office or position. 

  • A vertex having a directed path to another vertex 

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