par·ti·san / ˈpärtəzən/ • n. 1. a strong supporter of a party, cause, or person.2. a member of an armed group formed to fight secretly against an occupying force, in particular one operating in enemy-occupied Yugoslavia, Italy, and parts of eastern Europe in World War II.• adj. prejudiced in favor of a particular cause: newspapers have become increasingly partisan.DERIVATIVES: par·ti·san·ship / -ˌship/ n.

partisan zealous supporter XVI; guerrilla soldier or chief XVII. — F. — It. dial. partisano = It. partigiano, f. parte PART.