opportunity vs surety

opportunity

noun
  • A favorable circumstance or occasion. 

  • opportuneness 

  • A chance for advancement, progress or profit. 

surety

noun
  • A promise to pay a sum of money in the event that another person fails to fulfill an obligation. 

  • One who undertakes to pay money or perform other acts in the event that his principal fails therein. 

  • A substitute; a hostage. 

  • Evidence; confirmation; warrant. 

  • Certainty. 

  • That which makes sure; that which confirms; ground of confidence or security. 

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