progeniture vs spin-off

progeniture

noun
  • ancestry, lineage 

  • offspring, progeny 

  • procreation 

spin-off

noun
  • An offshoot. 

  • A fictional work where the protagonist was introduced in a preceding work or at least shares the same setting, often in a different aspect. 

  • By-product. 

  • The formation of a subsidiary company that continues the operations of part of the parent company; the company so formed. 

  • An incidental benefit or unexpected pay-off. 

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