The authors differ both on the origin and on the geographical distribution of this surname, which suggests the existence of independent clusters of origin (ceppi) arisen in different regions without direct relation between them.

E. Rossoni notes that the surname is concentrated mainly between the Verona, Mantua and Modena areas, with a secondary presence in the Alessandria area. He derives it from the medieval name Malvetius, documented in the Codice Diplomatico Bresciano in a text of 1197 drawn up in Brescia. Rossoni also records its fixing as a surname through a letter of 1509 written by Niccolò Machiavelli to Alamanno Salviati, in which a certain messer Luzio Malvezi is mentioned.

V. Blunda proposes a completely different etymology for the Sicilian variant: the dialect word marvìzzu, which designates the thrush, a migratory bird much prized in the autumn hunting of Sicily. As a surname it would have arisen from a nickname applied to the hunter who specialized in catching it, or else by comparison with the call or the movements of the animal.