Other forms: hamartias
The word hamartia refers to a flaw or mistake that leads to a fictional character's downfall. Classical tragedies revolve around the main character's hamartia, the tragic flaw that sets a series of disastrous events in motion.
Achilles’ heel was his hamartia – his fatal flaw. Most tragedies couldn’t exist without hamartia. It’s in the tragic plays of the ancient Greek writer Aeschylus to works like Shakespeare's Hamlet and Romeo and Juliet. In Shakespeare, examples of hamartia are Hamlet's indecisiveness and Juliet's blind loyalty to Romeo. Hamartia comes from a root meaning "to miss or fail."