lassitude vs slothfulness

lassitude

noun
  • Listlessness or languor. 

  • Lethargy or lack of energy; fatigue. 

slothfulness

noun
  • The result or product of being slothful. 

  • The state or quality of being slothful. 

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