The authors agree that this surname has a toponymic origin, linked mainly to the municipality of Gerace, in the province of Reggio Calabria, in Calabria. E. De Felice notes that it also derives, in part, from Gerace Marina —the official name of present-day Locri until 1934— and, in Sicily, from the place name Geraci Siculo, in the province of Palermo, together with their corresponding demonyms. For De Felice, the variants with an initial I- reflect the local Greek forms Ieràki and Ieràci of the place name, derived from the Byzantine Hagia Kyriaké, meaning "Saint Kyriake".

G. Rohlfs offers a different perspective on the etymology: he links the place name Gerace directly to the Greek ἱεράκι, meaning "sparrowhawk", and notes that in Greece the surname Gerakis survives as a kindred form. Rohlfs highlights the Greek-Byzantine character of the surname, present throughout Calabria and also in Sicily, and considers it a sister form of Geraci, referring also to the variants Hjeraci and Jerace.

E. Rossoni gathers both interpretative lines: on the one hand, the toponymic origin in Gerace and Gerace Marina; on the other, the possibility that the surname is the Italianization of the Greek surname Gerakis, derived in turn from the term ieraki meaning "sparrowhawk". Rossoni also provides a concrete historical fact: the transformation into a surname is documented in the second half of the 17th century in Bovalino, in the province of Reggio Calabria, with the notary Horatius Ranerius de Gerace.

In synthesis, the sources diverge as to the ultimate etymon of the place name: De Felice traces it to the Byzantine Hagia Kyriaké, while Rohlfs and Rossoni link it to the Greek ἱεράκι ("sparrowhawk"). Both traditions point, in any case, to the deep Greek-Byzantine substratum of this surname, characteristic of Calabria and present also in Sicily.