stiffness vs warmth

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. 

warmth

noun
  • Fervor, intensity of emotion or expression. 

  • Friendliness, kindness or affection. 

  • A moderate degree of heat; the sensation of being warm. 

  • The effect of using mostly red and yellow hues. 

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