crash pad vs rooming house

crash pad

noun
  • Any place used for temporary lodging, especially without payment or permission. 

  • A room where one can recover after a bad acid trip. 

  • A protective foam pad placed on the ground, used as protection in case of falling from the wall. 

  • A place of temporary lodging for airline flight crews. 

rooming house

noun
  • A building with small, basic, inexpensive apartments for rent, often without en-suite bathrooms. 

  • A house which lets out furnished apartments. 

How often have the words crash pad and rooming house occurred in a corpus of books? (source: Google Ngram Viewer )