court card vs trade card

court card

noun
  • A king, queen, or jack/knave card in a standard deck of playing cards. 

  • A postcard measuring approximately 4·75″ × 3·5″, in use mainly in the United Kingdom circa 1894–1902. 

trade card

noun
  • A trading card (such as a cigarette card). 

  • An early precursor of the business card, first produced at the beginning of the seventeenth century. 

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