garbage collection vs garbage woman

garbage collection

noun
  • A service, generally run by local government, for transporting household garbage to the appropriate facility. 

  • An automatic mechanism that frees up resources (such as allocated memory) that are no longer in use. 

garbage woman

noun
  • A female garbage collector. 

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