dramaturge vs ghostwriter

dramaturge

noun
  • A literary adviser or editor in a theater, opera, or film company that researches, selects, adapts, edits, and interprets scripts, libretti, texts, and printed programs (or helps others with these tasks), consults with authors, and does public relations work. 

  • Someone who writes or adapts theater plays, a playwright, dramatist, especially one connected with a specific theater or company. 

verb
  • To act as a dramaturge. 

ghostwriter

noun
  • A professional writer who is paid to write material that is officially credited to another person; one who writes on behalf of someone else, often for a celebrity. 

  • Smith was listed as the author of his autobiography, but a ghostwriter did most of the work. 

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