crisis vs emergency

crisis

noun
  • An unstable situation, in political, social, economic or military affairs, especially one involving an impending abrupt change. 

  • A crucial or decisive point or situation; a turning point. 

  • A traumatic or stressful change in a person's life. 

  • A sudden change in the course of a disease, usually at which point the patient is expected to either recover or die. 

  • A point in a drama at which a conflict reaches a peak before being resolved. 

emergency

noun
  • A situation which poses an immediate risk and which requires urgent attention. 

  • Arising from or used in an emergency. 

  • An individual brought in at short notice to replace a member of staff, a player in a sporting team, etc. 

  • The department of a hospital that treats emergencies. 

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