attic vs catacomb

attic

noun
  • A person's head or brain. 

  • The space, often unfinished and with sloped walls, directly below the roof in the uppermost part of a house or other building, generally used for storage or habitation. 

catacomb

noun
  • An underground system of tunnels and chambers with recesses for graves, used (in former times) as a cemetery; a tunnel system used for burying the dead, as in Paris or Ancient Rome. 

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