catacomb vs graveyard

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. 

graveyard

noun
  • A tract of land in which the dead are buried. 

  • The discard pile, in some trading card games. 

  • A team where players are sent when they are not useful, or a team where players become useless if sent there. 

  • Synonym of suicide (“beverage combining all available flavors at a soda fountain”) 

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