The authors agree that it is a typically Sicilian surname, with presence concentrated in the areas of Catania, Messina and Enna. F. Miranda also details its extension to other regions such as Lombardy, Piedmont, Tuscany, Lazio, Veneto, Emilia-Romagna, Liguria, Campania, Calabria and Abruzzo.

On the etymology there are different interpretations. E. Rossoni and Miranda agree that the surname derives from the medieval dialectal form Anfusus, in turn from Anfossus, an archaic form of the name of Gothic origin Alfonso, composed of adal or athal ("noble, brave") and funs ("prepared"), with the general sense of "brave in battle". Rossoni and Miranda also note a second hypothesis: the derivation from the Calabrian dialectal term nfusu, meaning "wet".

V. Blunda proposes a different etymology: he considers that the surname is of Arabic origin, a legacy of the Emirate of Sicily (827–1091), and derives it from the etymon anfus, meaning "most prized, most sought after". This interpretation is not shared by the other authors.