Maddyn is a modern American spelling of Madden and Madison, a surname that means "son of Maud"; Maud itself is a medieval form of Matilda, "mighty in battle". The -yn ending echoes Madelyn and Brooklyn. Maddyn is rare but rising slowly: it has climbed from number 2872 in 2015 to number 2313 in 2025, its best US rank so far.