V. Blunda and N. Bergamo differ on the origin of the surname.

Blunda, for the Sicilian variant, derives it from the Germanic personal name Racco, a phonetic variant of Racca with the open vocalization characteristic of medieval southern Italian. He notes that the simple form of the anthroponym is preserved especially in areas of southern Italy, where Lombard anthroponymy arrived through the Duchy of Benevento and remained alive in the medieval notarial records. The onomastic base is the same as that of the surname Racca, possibly connected to the roots rad or ragin in their reduced hypocoristic form without a second compositional element.

Bergamo, on the other hand, proposes a Greek origin, from the terms rhakos ("rag") or rhakhis ("back").