poker face vs potato

poker face

noun
  • Any similar expression used to prevent giving away one's motives, feelings, or situation. 

  • An impassive facial expression cultivated to prevent other players from determining whether one's actions in the game are the result of a quality hand, or of bluffing. 

potato

noun
  • Metaphor for a person or thing of little value. 

  • A camera that takes poor-quality pictures. 

  • A mentally handicapped person. 

  • A conspicuous hole in a sock or stocking. 

  • The tuber of a plant, Solanum tuberosum, eaten as a starchy vegetable, particularly in the Americas and Europe; this plant. 

  • An underpowered computer or other device, especially when small in size. 

adj
  • Underpowered; low-end. 

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