fledge vs preen

fledge

verb
  • To grow, cover or be covered with feathers. 

  • To complete the last moult and become a winged adult insect. 

  • To decorate with feathers. 

  • To care for a young bird until it is capable of flight. 

preen

verb
  • To groom; to trim or dress with the beak, as the feathers. 

  • To spend time making oneself attractive and admiring one's appearance, e.g. in front of a mirror. 

  • To trim up, as trees. 

  • To improve the appearance of; groom; prettify. 

  • To flatter. 

  • To comb; to make orderly. 

  • To show off, posture, or smarm. 

  • To pin; fasten. 

noun
  • bodkin; brooch 

  • A forked tool used by clothiers for dressing cloth. 

  • pin 

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