outbreak

/ˈaʊtbreɪk/
noun
  1. A sudden start or increase of something bad, such as a disease, war, or violence.
    • Health officials are monitoring the outbreak of a new virus in the region.
    • An outbreak of fighting between the two groups led to many injuries.
    • The government acted quickly to contain the outbreak of the flu.
  2. A sudden, strong expression of an emotion or activity.
    • There was an outbreak of laughter when the clown slipped on the banana peel.
    • The news caused an outbreak of panic among the residents.
    • Her speech triggered an outbreak of applause from the audience.