Look up emergency in Wiktionary, the free dictionary.

An emergency medical technician treats a woman who has collapsed in the street in New York. Dangers to life and health are serious enough that emergency response systems are considered vital.

Emergency slides are deployed after the crash landing of British Airways Flight 38

An emergency is a situation that poses an immediate risk to health, life, property, or environment.^[1] Most emergencies require urgent intervention to prevent a worsening of the situation, although in some situations, mitigation may not be possible and agencies may only be able to offer palliative care for the aftermath.

While some emergencies are self-evident (such as a natural disaster that threatens many lives), many smaller incidents require that an observer (or affected party) decide whether it qualifies as an emergency. The precise definition of an emergency, the agencies involved and the procedures used, vary by jurisdiction, and this is usually set by the government, whose agencies (emergency services) are responsible for emergency planning and management.