Gaddo is a Florentine variation of the Italian given name Gerardo (Gerard).
Famous persons with the given name Gaddo Gaddo Gaddi Florentine painter and mosaicist (c. 1250–1327/30?) Gaddo della Gherardesca Tuscan aristocrat, formerly associated romantically with Sarah, Duchess of York Gaddo, son of Ugolino della Gherardesca (c. 1220–1289), and who features in Dante's Inferno