The authors agree in pointing to Gemona del Friuli, in the province of Udine, as the main core of this surname, with a documented presence also in Venzone, Artegna, Forgaria, Tolmezzo and Pordenone. E. Rossoni adds a specific area in Casalmaggiore, in the Cremona area.

E. Costantini considers the surname difficult to explain and notes that in 1575 it was written Choi. E. De Stefani goes deeper into the etymology and sets out two interpretative paths. The first links it to the Slovene element -goi / -goj, documented from at least the 10th century in Carinthia and Styria, and connected with the Slovene verb gojiti ("to cultivate, to tend") or, in some cases, with the Lombard word gahago, which gave the Slovene gaj ("small wood"). This hypothesis rests on surnames such as Cicigoi and Saligoi, found in areas of Friuli with Slavic influence.

De Stefani warns, however, that the Goi of the Gemona area and of Carnia are distributed in non-Slavic areas, and that the surnames in -goi of the eastern areas cannot be reduced to the simple form Goi, which suggests a different history for the Goi of Gemona. The etymological question is not fully settled. Rossoni, for his part, proposes that the surname could derive from a nickname related to the place of origin, where goi designates, in the dialect of the region of Lombardy, a very deep, hollowed-out stretch of a torrent.