n[U]
[Date: 1800-1900; Origin: hysteric 'hysterical' (17-20 centuries), from Latin hystericus, from Greek hystera ( HYSTERECTOMY); because it was believed hysteria was caused by the uterus]
extreme excitement that makes people cry, laugh, shout etc in a way that is out of control
　In a fit of hysteria, Silvia blamed me for causing her father's death.
a situation in which a lot of people feel fear, anger, or excitement, which makes them behave in an unreasonable way
　Since the General's death, the population has been gripped by mass hysteria .
medical a medical condition which upsets someone's emotions and makes them suddenly feel very nervous, excited, anxious etc