Absolutely rare it is Neapolitan. additions provided by Fabio Paolucci Cuordifede is a very rare surname, present only in Naples and probably belonging to a single family unit. From the etymological point of view it is clear the derivation from a nickname linked to a character peculiarity of the progenitor inclined often to do good. It would not be possible to exclude the recent formation of the surname in ecclesiastical circles, where very often the so-called sons of no-one or sons of sin who were saved and then raised by friars and nuns were abandoned: these were also given the task of giving a name and a surname to the unfortunate rescued infants and more often than not, in addition to the usual Esposito, Proietti or degli Infanti, they assigned names related to Christianity (names of Saints of the day of the finding or names dictated by the Catholic spirit, as can be, in this case, the 'cognominato expression Cuor di fede).
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