materialist vs unbeliever

materialist

noun
  • Someone who is materialistic, concerned only with material possessions. 

  • A follower or proponent of philosophical materialism. 

adj
  • Having features typical of philosophical materialism. 

unbeliever

noun
  • One who does not believe, particularly in a deity (used by believers to describe people who do not believe in the same deity or deities as themselves). 

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