adherent vs believer

adherent

noun
  • A person who has membership in some group, association or religion. 

adj
  • Adhesive, sticking to something. 

  • Having the quality of clinging or sticking fast to something. 

  • Attaching or pressing against a different organ. 

believer

noun
  • A person who believes; especially regarding religion. 

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