casualty vs mortality

casualty

noun
  • Specifically, a person who has been killed (not only injured) due to an accident or through an act of violence; a fatality. 

  • Something that happens by chance, especially an unfortunate event; an accident, a disaster. 

  • An incidental charge or payment. 

  • A person in military service who becomes unavailable for duty, for any reason (notably death, injury, illness, capture, or desertion). 

  • The accident and emergency department of a hospital providing immediate treatment; a casualty department or emergency room. 

  • A person suffering from injuries or who has been killed due to an accident or through an act of violence. 

  • Someone or something adversely affected by a decision, event or situation. 

mortality

noun
  • Deaths resulting from an event (such as a war, epidemic or disaster). 

  • The number of deaths per given unit of population over a given period of time. 

  • Death. 

  • The state of being susceptible to death. 

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