crash pad vs shelter

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. 

shelter

noun
  • An institution that provides temporary housing for homeless people, battered women, etc. 

  • A refuge, haven or other cover or protection from something. 

verb
  • To take cover. 

  • To provide cover from damage or harassment; to shield; to protect. 

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