Caiumi is typical of Modena and Carpi in the Modena area and of Reggio Emilia, Cajumi is almost unique, should derive from an alteration of the Hebrew name Caim (Cain), the name Caium exists among the Arabs of North Africa as an archaic form of Caim, absolutely unlikely the hypothesis that it may derive from the accusative form Caium of the Latin praenomen Caius.
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