fledgling vs yearling

fledgling

noun
  • An insect that has just fledged, i.e. undergone its final moult to become an adult or imago. 

  • A young bird which has just developed its flight feathers (notably wings). 

  • An immature, naïve or inexperienced person. 

adj
  • Emergent or rising. 

  • Untried or inexperienced. 

yearling

noun
  • An animal that is between one and two years old; one that is in its second year (but not yet two full years old). 

  • A racehorse that is considered to be one year old until a subsequent January 1st. 

  • A sophomore at West Point military academy. 

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