big house vs stalag

big house

noun
  • Prison, jail. 

  • Used other than figuratively or idiomatically: see big, house. 

  • A religious building of the Delaware Indians, representing the cosmos. 

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 big house and stalag occurred in a corpus of books? (source: Google Ngram Viewer )