E. Rossoni links this surname with the ancient Greek name Phalces or with the Latin cognomen Falx, and places it as native to the Salerno area.

V. Blunda considers it a Sicilian surname of dialectal origin, derived from the word fàuci, which in the local dialect designates the "sickle", the curved instrument with a serrated blade used in the reaping of cereals. According to Blunda, as a surname it could have originated in the trade of the blacksmith who made these tools or in that of the professional reaper. He records this entry together with Fauci, treating them as graphic variants of the same etymon that remained as independent surnames.

The two proposals are independent of each other: Rossoni points to an origin in the Latin-Greek proper name or cognomen in the region of Campania, while Blunda proposes an occupational origin in Sicily from the dialectal lexicon, which suggests that the surname presents independent clusters of origin (ceppi) arisen in different regions without direct relation between them.