Duce is an Italian word meaning "leader" (derived from Latin dux of the same meaning).

As early as 1923, Italian prime minister Benito Mussolini adopted the name Il Duce, as his de facto title in an attempt to elevate himself to a position as the nation's unquestioned supreme leader. It was similar to German Chancellor Adolf Hitler's title as "Führer" of Germany, although unlike Mussolini, Hitler actually made Führer a post in the German government.

Other Italian 'leaders' whose names derive from dux are the Doges of Venice and Genoa, and the title of nobility duca ('duke').