E. Rossoni proposes that this surname derives from a dialectal modification of the Greek name Foca. He recalls that with that name Saint Phocas of Antioch is venerated, a martyr under the emperor Trajan in the year 107. Geographically, Rossoni identifies a main zone in the province of Agrigento —with presence in Aragona, Favara, Agrigento and Racalmuto— and a probably secondary zone in the province of Reggio Calabria, in Bagnara Calabra.

G. Rohlfs agrees on the Greek origin, although he specifies that it is a surname of Greek-Byzantine root, and considers it a variant of Focà. He notes its presence in the province of Catanzaro —in Pizzo— and in the province of Reggio Calabria —in Palmi, Scilla and the Aspromonte area—. He adds that in Greece the form Φουκᾶς survives as a surname, and that in some contexts the graphic accent may be lost, giving the form Fuca.