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tritagonist

n. In Greek drama, the actor who played the third role (after the protagonist and deuteragonist)

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Tritagonist

In literature, the tritagonist (from , tritagōnistḗs, third actor) is the third most important character of a narrative, after the protagonist and deuteragonist. In Ancient Greek drama, the tritagonist was the third member of the acting troupe.

As a character, a tritagonist may act as the instigator or cause of the sufferings of the protagonist. Despite being the least sympathetic character of the drama, he or she occasions the situations by which pity and sympathy for the protagonist are excited.