central vs exterior

central

noun
  • centre 

adj
  • Having or containing the centre of something. 

  • Being in the centre. 

  • Exerting its action towards the peripheral organs. 

  • Being very important, or key to something. 

exterior

adj
  • Being from outside a country; foreign. 

  • Outdoor. 

  • Relating to the outside parts or surface of something. 

noun
  • Foreign lands. 

  • The outside part, parts or surface of something. 

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