ennui vs weariness

ennui

noun
  • A gripping listlessness or melancholia caused by boredom; depression. 

verb
  • To make bored or listless; to weary. 

weariness

noun
  • Exhaustion, fatigue or tiredness. 

  • A lack of interest or excitement. 

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