four-flush vs play possum

four-flush

verb
  • To bluff. 

  • To attempt to pass off a four-flush as a flush. 

noun
  • Four cards of the same suit. 

play possum

verb
  • To feign death; to remain quiet and still to escape attention or remain undetected; to lie low. 

  • To feign sleep, illness, etc. 

How often have the words four-flush and play possum occurred in a corpus of books? (source: Google Ngram Viewer )