A Greek word from a verb meaning ‘to purify’, ‘to cleanse’, or even ‘to purge’, used in drama studies to describe a peak moment in a play when a sequence is brought to a close in such a way as to prompt laughter, tears, or some other form of affective and emotional release. The term was first used by Aristotle in his Poetics, which is generally thought to have been written in reply to Plato’s hostile view of poetry and drama as something that induces hysteria in men. Borrowing the term from medicine, where it was used to describe menstruation, Aristotle argued that, contrary to Plato, poetry and drama enable men to expel their hysterical emotions, effectively making them stronger not weaker.