The authors agree that the surname derives from nicknames or trade names related to the activity of the charcoal-burner —producer, extractor or seller of charcoal—. E. De Felice notes that these forms continue medieval names built on carbone, carbonàio or carbonaro, and that the surname is widely spread throughout Italy, including Sardinia, where the variant Carboni is very frequent in the Campidano and in the Sassari area. He adds that the derived and altered forms —except Carbonìn, peculiar to northern Italy— are characteristic of the centre and south of the country.

F. Miranda incorporates an additional dimension: the surname could also go back to the Latin cognomen Carbo-Carbonis, or derive from Italian place names such as Carbone, in the province of Potenza, Carbonara, in the Bari area, and Pizzo Carbonara, in the Palermo area. He highlights its presence in southern Italy, especially in Campania, Puglia, Sicily, Calabria and Basilicata, although it is also recorded in Lombardy, Lazio, Piedmont, Liguria, Tuscany and Emilia-Romagna.

V. Blunda, from a Sicilian perspective, proposes a Greek etymon: the term càrbon, which designated charcoal as an essential fuel in ancient cooking and forging. According to this source, the surname functioned originally as a nickname referring to the trade of the ancestor or to his dark complexion, and then became a surname through family transmission.