Both typically Lombard, Calderoli is Bergamo, Bergamo and Azzano San Paolo, Caldiroli, more widespread, is specific to the area between Milan and Varese, Castellanza, Gorla Minore and Busto Arsizio in the Varese area and Legnano in the Milan area, should derive from the word Lombard caldera (large copper pot normally used to heat water for laundry), would probably indicate the activity of producer, or repairer of calderas carried out by the founders.
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