coextensive vs relating

coextensive

adj
  • Having the same spatial limits or boundaries; sharing the same area. 

  • Occurring over the same period of time; contemporaneous. 

  • Having the same extension—the object or set of objects to which a term refers. 

relating

noun
  • The act of relating, or forming or identifying relationships; relation. 

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