The definition of a hysteria is a craze or a state of extreme emotional excitement or upset.(noun)
When everyone is in a panic about a potential upcoming storm, this is an example of a time when there is great hysteria about the storm.
See hysteria in Webster's New World College Dictionary
Origin: ModL < hysteric + -ia
See hysteria in American Heritage Dictionary 4
Origin: New Latin
Origin: : hyster(ic)
Origin: + -ia1.
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