eruption vs myoclonus

eruption

noun
  • A sudden release of pressure or tension. 

  • A violent ejection, such as the spurting out of lava from a volcano. 

  • An infection of the skin resulting in a rash or blemishing. 

myoclonus

noun
  • The brief, involuntary twitching of a muscle or group of muscles. 

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