cathedral vs metropole

cathedral

noun
  • A large, impressive, lofty, and/or important building or place of some other kind. 

  • A large or important church building. 

  • The principal church of an archbishop's/bishop's archdiocese/diocese which contains an episcopal throne. 

  • A large buttressed structure built by certain termites. 

name
  • In certain right-wing conspiracy theories, the mainstream system or establishment of society, held to be liberal or leftist and to be working against the interests of the people or nation, which is both. 

adj
  • Relating to the throne or the see of a bishop. 

metropole

noun
  • A metropolis; the main city of a country or area. 

  • The parent-state of a colony. 

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