the Greek word for error or failure, used by Aristotle in his Poetics (4th century BCE) to designate the false step that leads the protagonist in a tragedy to his or her downfall. The term has often been translated as ‘tragic flaw’, but this misleadingly confines the cause of the reversal of fortunes to some personal defect of character, whereas Aristotle's emphasis was rather upon the protagonist's action, which could be brought about by misjudgement, ignorance, or some other cause.

Oxford Dictionary of Literary Terms via Answers.com

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