courtyard vs lawn

courtyard

noun
  • An area, open to the sky, partially or wholly surrounded by walls or buildings. 

lawn

noun
  • An open space between woods. 

  • Ground (generally in front of or around a house) covered with grass kept closely mown. 

  • An overgrown agar culture, such that no separation between single colonies exists. 

  • A type of thin linen or cotton. 

  • Pieces of this fabric, especially as used for the sleeves of a bishop. 

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