ennui vs malaise

ennui

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

verb
  • To make bored or listless; to weary. 

malaise

noun
  • A feeling of general bodily discomfort, fatigue or unpleasantness, often at the onset of illness. 

  • An ambiguous feeling of mental or moral depression. 

  • Ill will or hurtful feelings for others or someone. 

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