Fedi is decidedly Tuscan, widespread in Pistoia, Prato, Florence, Livorno and Grosseto and in their provinces, Feda and Federella are both extremely rare and it is impossible to identify their area of origin. A possible derivation could be from the Latin word Fadia or Fadius modified by the dialect, another hypothesis, more probable, could be a derivation from the medieval word feda, fedus (ugly, ugly).
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