stipulation vs wild card

stipulation

noun
  • Something that is stated or stipulated as a condition of an agreement. 

  • The situation, arrangement, and structure of the stipules. 

  • The act of stipulating; a contracting or bargaining; an agreement. 

  • A goal to be achieved in a chess problem; for example, to checkmate Black within a specified number of moves. 

wild card

noun
  • A card that can be assigned any value or used to substitute for any needed card. 

  • A competitor or team that is allowed to compete in a tournament despite not reaching the normal standards to qualify for inclusion. 

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