layperson vs nonprofessional

layperson

noun
  • One who is not intimately familiar with a given subject or activity. 

  • A person who is not a cleric. 

nonprofessional

noun
  • One who is not a professional; an amateur. 

adj
  • not professional; amateur 

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