The authors agree that the surname derives from the medieval term cappa, meaning "cloak" or outer garment, used originally as a nickname before becoming a family surname. E. Rossoni notes that it is present throughout Italy, with greater diffusion in the Lombardy and Piedmont areas, and documents the word as early as 1185.

V. Blunda traces the term to the Greek cappa, with the sense of "cloak with a hood", a garment used in cold climates or as a religious habit. In the Sicilian context, the nickname would have been applied to the ancestor for his characteristic clothing or for a trade linked to that garment, and over time it became a family surname.