The surname presents divergent origins according to the authors consulted.

E. Rossoni maintains that in most cases it would derive from the medieval name Cannonus, documented as early as Antiquity with the Athenian statesman and legislator Cannonus —cited also by Xenophon— and, in more recent times, with the 13th-century merchant and banker Cannonus de Ganducio, in the Alessandria area. In some cases, Rossoni notes, it could derive from place names with the root Canne or Cannone. The form Cannone is recorded mainly in Lazio, Puglia, the Ascoli Piceno area in the Marche, the Chieti area in Abruzzo, the Naples area in Campania and in Sicily; the variant Cannoni appears in the Florence, Arezzo and Siena area in Tuscany, in the Perugia area in Umbria, in Rome and in the Sassari area in Sardinia.

V. Blunda, on the other hand, proposes for the Sicilian form an Arabic origin: it would derive from the etymon al kanuni, meaning "brazier, small stove", and would have functioned as an occupational nickname linked to trades that used fire, or as a descriptive nickname alluding to an ardent character.