Harlequin (/ˈhɑːrləkwɪn/; Italian: Arlecchino [arlekˈkiːno], French: Arlequin [aʁləkɛ̃], Old French Harlequin) is the best-known of the zanni or comic servant characters from the Italian Commedia dell'arte. The role is traditionally believed to have been introduced by Zan Ganassa in the late 16th century, was definitively popularized by the Italian actor Tristano Martinelli in Paris in 1584–1585, and became a after Martinelli's death in 1630.
The Harlequin is characterized by his chequered costume. His role is that of a light-hearted, nimble, and astute servant, often acting to thwart the plans of his master, and pursuing his own love interest, Columbina, with wit and resourcefulness, often competing with the sterner and melancholic Pierrot. He later develops into a prototype of the romantic hero. Harlequin inherits his physical agility and his trickster qualities, as well as his name, from a mischievous "devil" character in medieval passion plays.