debt vs payoff

debt

noun
  • Money that one person or entity owes or is required to pay to another, generally as a result of a loan or other financial transaction. 

  • An action, state of mind, or object one has an obligation to perform for another, adopt toward another, or give to another. 

  • The state or condition of owing something to another. 

  • An action at law to recover a certain specified sum of money alleged to be due 

payoff

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