E. Rossoni proposes that the surname would derive from a nickname based on the Sicilian dialectal term facci d'omo, which designates the barn owl or belfry owl, and places it in the zone comprised between Palermo and Agrigento.

V. Blunda develops this same base in greater detail: the dialectal compound fàcci d'òmu means literally "face of a man" and is the Sicilian popular denomination both of the eagle owl and of the common barn owl. The association responds to the anthropomorphisation of the face of the bird, whose rounded facial disc and large eyes of fixed gaze evoke a human countenance. As a surname, Blunda considers that it could have originated in a nickname applied to a person of a broad face and penetrating gaze, or linked to the beliefs of ill omen that surround these nocturnal raptors in popular tradition.