copycat vs counterfeit

copycat

noun
  • One who imitates or plagiarizes others' work. 

  • A criminal who imitates the crimes of another; specifically, a criminal who commits the same crime, especially a highly-publicized one, that has just been or recently committed by someone else. 

verb
  • To act as a copycat; to copy in a shameless or derivative way 

adj
  • Imitative; unoriginal. 

counterfeit

noun
  • One who counterfeits; a counterfeiter. 

  • A non-genuine article; a fake. 

adj
  • Inauthentic. 

  • False, especially of money; intended to deceive or carry appearance of being genuine. 

  • Assuming the appearance of something; deceitful; hypocritical. 

verb
  • To falsely produce what appears to be official or valid; to produce a forged copy of. 

  • Of a turn or river card, to invalidate a player's hand by making a better hand on the board. 

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