pigpen vs scrapheap

pigpen

noun
  • Something extremely dirty or messy. 

  • A pigsty; an enclosure where pigs are kept. 

  • The pigpen cipher. 

scrapheap

noun
  • A pile in which junk is discarded. 

  • A junkyard. 

  • A collection of discarded or rejected items or ideas. 

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