Don (Spanish: [ˈdon], Italian: [ˈdɔn], Portuguese: Dom [ˈdõ]) from Latin dominus, is an honorific title used in Iberia and Italy. The female equivalent is doña (Spanish: [ˈdoɲa]), Donna (Italian: [ˈdɔnna]), and Dona (Portuguese: [ˈdonɐ]), abbreviated "Dª" or simply "D."
Although originally a title reserved for royalty, select nobles, and church hierarchs, it is now often used as a mark of esteem for a person of personal, social or official distinction, such as a community leader of long standing, a person of significant wealth, or a noble, but may also be used ironically. As a style, rather than a title or rank, it is used with, and not instead of, a person's name.
Syntactically, it is used in much the same way (although for a broader group of persons) as "Sir" and "Dame" are used in English when speaking of or to a person who has been knighted, e.g. "Don Firstname" or "Doña Firstname Lastname". Unlike "The Honourable" in English, Don may be used when speaking directly to a person, and unlike "Mister" it must be used with a given name. For example, "Don Diego de la Vega," or (abbreviating "señor") "Sr. Don Diego de la Vega," or simply "Don Diego" (the secret identity of Zorro) are