promising vs rookie

promising

adj
  • a promising young apprentice 

  • Showing promise, and likely to develop in a desirable fashion. 

  • Encouraging and inspiring confidence. 

noun
  • The act of making a promise. 

rookie

adj
  • non-professional; amateur 

noun
  • A type of firecracker, used by farmers to scare rooks. 

  • A novice. 

  • An athlete either new to the sport or to a team or in his first year of professional competition, especially said of baseball, basketball, hockey and American football players. 

  • An inexperienced recruit, especially in the police or armed forces. 

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