From the Greek "hystera" = uterus. For a few thousand years until the late nineteenth century, hysteria referred to a medical condition thought to be particular to women and caused by disturbances of the uterus.
Definitions include: uncontrollably emotional; irrational from fear,
emotion, or an emotional shock; very funny as from hysterical or
uncontrollable fits of laughter.
In psychology they say it is a disorder in which a psychological
conflict is converted into a bodily disturbance.
During the 1800s it was decided that men could also be hysterical.
In time it could be applied to anyone as the definition expanded to
be an emotional state, rather than a physical state.
Incidently, the Oxford English Dictionary says the colloquial
term 'hissy fit' for someone would go into hysterics and throw a
tantrum if they didn't get their way. comes from hysteria.