central vs regional

central

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. 

noun
  • centre 

regional

adj
  • Of, or pertaining to, one part of the body. 

  • Of, or pertaining to, a specific region or district. 

  • Of a state or other geographic area, those parts which are not metropolitan, but are somewhat densely populated and usually contain a number of significant towns. 

  • Of, or pertaining to, a large geographic region. 

noun
  • An entity or event with scope limited to a single region. 

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