preen vs spiff

preen

verb
  • To improve the appearance of; groom; prettify. 

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

  • To trim up, as trees. 

  • To flatter. 

  • To comb; to make orderly. 

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

  • To show off, posture, or smarm. 

  • To pin; fasten. 

noun
  • bodkin; brooch 

  • A forked tool used by clothiers for dressing cloth. 

  • pin 

spiff

verb
  • (usually with up or out) To make spiffy (attractive, polished, or up-to-date) 

  • To reward (a salesperson) with a spiff or bonus. 

  • To throw; to heave. 

  • To attach a spiff or bonus to the selling of (a product) 

noun
  • Attractiveness or charm in dress, appearance, or manner. 

  • A bonus or other remuneration, given for reaching a sales goal or promoting the goods of a particular manufacturer. Originally from textile retailing, a percentage given for selling off surplus or out-of-fashion stock, of which the sales person could offer part as a discount to a customer. 

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