nightmare vs scare

nightmare

noun
  • Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure. 

  • A very bad or frightening dream. 

  • A feeling of extreme anxiety or suffocation experienced during sleep; Sleep paralysis. 

verb
  • To have a nightmare. 

scare

noun
  • A cause of slight terror; something that inspires fear or dread. 

  • A minor fright. 

  • A device or object used to frighten. 

verb
  • To frighten, terrify, startle, especially in a minor way. 

adj
  • lean; scanty 

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