recursion vs reversal

recursion

noun
  • The act of recurring. 

  • The act of defining an object (usually a function) in terms of that object itself. 

  • The invocation of a procedure from within itself. 

reversal

noun
  • An instance of reversing. 

  • A change in fortune; a change from being successful to having problems. 

  • The state of being reversed. 

adj
  • Intended to reverse; implying reversal. 

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