Panzera is panitalian, Panzeri is specific to Lombardy, Panzerini, absolutely rare, is from the lower Brescia area, Panzironi is specific to the Romans, to Rome and Zagarolo in particular, but also to Monteporzio Catone, San Cesareo and Frascati, should derive, directly or through hypocoristic or accretive forms, from nicknames originated from the presence of an imposing belly in the progenitors. additions provided by Giovanni Vezzelli Panzeri, Panzera, reference to "who made pancera, cuirasses". However, Lurati sees in the Panìcera variant a derivation from 'panizza', "focaccia", to indicate who made it (see Panizza).
You may be interested
Verba Volant, Scripta Manent