aftershock vs repercussion

aftershock

noun
  • By extension, any result or consequence following a major event. 

  • An earthquake that follows in the same vicinity as another, usually larger, earthquake (the "mainshock"). 

  • Emotional and physical distress following a traumatic event. 

repercussion

noun
  • A consequence or ensuing result of some action. 

  • In a vaginal examination, the act of imparting through the uterine wall with the finger a shock to the foetus, so that it bounds upward, and falls back again against the examining finger. 

  • The subsidence of a tumour or eruption by the action of a repellent. 

  • The act of driving back, or the state of being driven back; reflection; reverberation. 

  • Rapid reiteration of the same sound. 

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