frigidity vs stiffness

frigidity

noun
  • Coldness of feeling, manner or quality; lack of ardor, animation or vivacity. 

  • The state of being frigid; coldness; lack of heat. 

  • Lack of natural heat and vigor of body; impotency. 

stiffness

noun
  • inelegance; a lack of relaxedness. 

  • rigidity or a measure of rigidity. 

  • inflexibility or a measure of inflexibility. 

  • muscular tension due to unaccustomed or excessive exercise or work; soreness. 

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