perquisite vs pro

perquisite

noun
  • A gratuity. 

  • Any monetary or other incidental benefit beyond salary. 

  • A privilege or possession held or claimed exclusively by a certain person, group or class. 

pro

noun
  • Professional. 

  • A prostitute. 

  • A professional sportsman. 

  • A chemical prophylaxis taken after sex to avoid contracting venereal disease. 

  • A person who supports a concept or principle. 

  • An advantage of something, especially when contrasted with its disadvantages (cons). 

prep
  • In favor of. 

adj
  • Professional. 

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