hesitation vs qualm

hesitation

noun
  • A faltering in speech; stammering. 

  • doubt; vacillation. 

  • An act of hesitating 

qualm

noun
  • A sudden sickly feeling; queasiness. 

  • A prick of the conscience; a moral scruple, a pang of guilt. 

  • A feeling of apprehension, doubt, fear etc. 

verb
  • To have a sickly feeling. 

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