Definitions
1.NounA situation which poses an immediate risk and which requires urgent attention."Cardiac arrest is an emergency requiring medical attention."
2.NounThe department of a hospital that treats emergencies.
3.NounA person brought in at short notice to replace a member of staff, a player in a sporting team, etc.
4.NounThe quality of being emergent; sudden or unexpected appearance; an unforeseen occurrence.
5.NounA critical urge to urinate or defecate.