dividing wall vs shutter

dividing wall

shutter

noun
  • The part of a camera, normally closed, that opens for a controlled period of time to let light in when taking a picture. 

  • One who shuts or closes something. 

  • Protective panels, usually wooden, placed over windows to block out the light. 

verb
  • To close shutters covering. 

  • To close up (a building) for a prolonged period of inoccupancy. 

  • To cancel or terminate. 

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