honor farm vs stalag

honor farm

noun
  • Synonym of prison farm 

stalag

noun
  • A German prisoner-of-war camp, especially in World War II. 

  • A genre of Nazi exploitation Holocaust pornography in Israel that flourished in the 1950s and early 1960s. 

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