barn vs threshing floor

barn

noun
  • A building, often found on a farm, used for storage or keeping animals such as cattle. 

  • An arena. 

  • A unit of surface area equal to 10⁻²⁸ square metres. 

  • A warm and cozy place, especially a bedroom; a roost. 

  • A child. 

verb
  • To lay up in a barn. 

threshing floor

noun
  • The floor of a threshing house or similar area where grain is threshed. 

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