earnest vs surety

earnest

noun
  • A sum of money paid in advance as a deposit; hence, a pledge, a guarantee, an indication of something to come. 

  • Gravity; serious purpose; earnestness. 

  • Seriousness; reality; actuality (as opposed to joking or pretence) 

verb
  • To be serious with; use in earnest. 

adj
  • Intent; focused; showing a lot of concentration. 

  • Serious or honest. 

  • Strenuous; diligent. 

  • Focused in the pursuit of an objective; eager to obtain or do. 

  • Serious; weighty; of a serious, weighty, or important nature; important. 

  • Possessing or characterised by seriousness. 

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 earnest and surety occurred in a corpus of books? (source: Google Ngram Viewer )