frater vs parson

frater

noun
  • A monk. 

  • A frater house. 

  • A comrade. 

parson

noun
  • A Protestant minister. 

  • An Anglican cleric having full legal control of a parish under ecclesiastical law; a rector. 

  • A Roman Catholic priest of an independent parish church. 

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