feretory vs larnax

feretory

noun
  • A receptacle that houses relics of saints. 

  • An area of a church where relics are kept. 

larnax

noun
  • A small closed coffin, box or cinerary urn often used as a container for human remains in Ancient Greece. 

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