billfold vs lizard

billfold

noun
  • A small, folding sleeve or case designed to hold paper currency, as well as credit cards, pictures, etc. 

lizard

noun
  • Lizard skin, the skin of these reptiles. 

  • A coward. 

  • A hand forming a "D" shape with the tips of the thumb and index finger touching (a handshape resembling a lizard), that beats paper and Spock and loses to rock and scissors in rock-paper-scissors-lizard-Spock. 

  • Any reptile of the order Squamata that is not a snake or an amphisbaenian, usually having four legs, external ear openings, movable eyelids and a long slender body and tail. 

  • A person who idly spends time in a specified place, especially a promiscuous female. 

  • An unctuous person. 

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