Both A. Bongioanni and E. Rossoni agree that the surname Michele — along with its many related forms — derives from the given name Michele, itself going back to the Hebrew Mi-Kha'El. Rossoni details the composition of the name: mi ("who"), kha ("like"), and El, a shortened form of Elohìm ("God"), yielding the overall sense of "he who is like God." Bongioanni records the traditional formulation as a question — "who is like God?" — and notes that the feast day falls on 29 September. It is also considered, in a complementary reading, that the name carries the sense of "who is as powerful and great as God."

Bongioanni documents the dialect forms attested in Friuli — Micél, Micelés, and Micelìn — from which the surnames Michelli, Michelés, Michelesio, Micés, Micesio, and Michelizza derive. For the area of Veneto he records the variants Chelini, Chelotti, Chelucci, and Chelli. In southern Italy he identifies Miceli as a characteristic form.

Rossoni broadens the geographical picture considerably. Micheletti is widespread in central and northern Italy, particularly in Lombardy and Tuscany, and also in Trentino — in the Val di Non and the Val d'Adige — with documentation going back to at least 1490. Micheli and Michelesio are likewise frequent in central and northern Italy, while Michelini extends across the north, Tuscany, the Marche, and Lazio. Micheletto is characteristically Venetian, and Michielotto is concentrated in the province of Padua.

Rossoni also adds a historical and literary note: the term micheletti designated Spanish soldiers of fortune and appears in several chapters of Alessandro Manzoni's novel I Promessi Sposi. He further records that the surname Michele itself is present in specific, localized areas of Italy in the provinces of L'Aquila, Benevento, and Potenza, and that Michelli has a presence in the area of Cavazzo Carnico — in the province of Udine — and in the area of Rapino, in the province of Chieti.