Hysterical means so taken over by emotion that you have lost control of yourself. Someone sobbing and gasping and unable to answer a simple question; a room of children laughing so hard they cannot stand up.
The word runs in two directions and the second one is casual. In everyday speech hysterical means extremely funny — the film was hysterical, his impression of the head teacher was hysterical — and that use belongs to friends, not to essays. The first sense is panic and grief: hysterical crying, hysterical with fear, a crowd that turned hysterical. Note the two set phrases pulling opposite ways: hysterical laughter can be either kind, while hysterically funny is only the good kind. Be careful aiming it at a person, because it carries a long history of dismissing women's distress and can land as an insult.
1adjectivehystericalUnable to control your emotions, especially through panic, fear or grief.
“She was hysterical by the time the ambulance arrived.”
2adjectivelaughingLaughing wildly and beyond control.
“One look at his hat and the whole table went hysterical.”
3adjectivehilariousExtremely funny.
“The last ten minutes of the play are hysterical.”
synonyms: hilarious
Hysterical is hysteric plus -al, from Latin hystericus and before that Ancient Greek ὑστερικός, glossed "suffering in the womb, hysterical", from ῠ̔στέρᾱ, "womb". Greek medicine blamed the condition on the womb, and so for centuries the word was aimed almost entirely at women. That history is why calling someone hysterical still sounds like a way of refusing to listen.
Ancient Greek
ὑστερικός — suffering in the womb, hysterical
Latin
hystericus
English, today
hysterical
Built from
From hysteric + al, from Latin hystericus, from Ancient Greek ὑστερικός (“suffering in the womb, hysterical”), from ῠ̔στέρᾱ (“womb”).
Etymology from Wiktionary, CC BY-SA