The authors differ significantly on the origin of this surname. E. Rossoni maintains that it would derive from a nickname that indicated the provenance of the founder of the lineage from a certain zone of the town, and considers it typical of the region of Campania, with presence in the Naples area and in the municipalities of Montefalcione and Candida, in the Avellino area.

V. Blunda, on the other hand, proposes for the Sicilian variant a Germanic origin, derived from the compound Gunda Radi, formed by gunda (combat, struggle) and radi (counsel, deliberation), meaning "counsellor in combat" or "wise for battle". Blunda warns that the popular interpretation which associates the surname with the Italian contrada (neighbourhood, section of a city) constitutes a crossed etymology: that common noun comes from the Low Latin contrata and bears no relation to the Germanic anthroponym. The root radi appears also in numerous European names such as Conrado, Riccardo or Roderico.

In synthesis, the surname presents at least two independent clusters of origin (ceppi), with different etymological explanations according to the region: one of a toponymic or descriptive base in Campania, and another of Germanic root in Sicily.