Some people only need one name to get the point across. Among this echelon are some of the greatest within their discipline: Pelé, Slash, Cher, Bono, and Flea, to name a few.
But then there's Madonna, who seems to hover above nearly all other one-namers in pop-culture history. And maybe all of history (sorry, Voltaire).
But she does have a last name, and in fact, she's never changed her name. What's Madonna's surname?
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