The authors agree that this surname derives from the Greek personal name bárbaros, which originally designated someone who spoke in an incomprehensible way —by the repeated sound bar bar— and by extension meant "foreigner". Through devotion to Saint Barbara, the name entered Christian onomastics and over time became a surname.

E. Rossoni notes that the form Barbara is typically southern, with presence in Rome, the Naples area, the Bari area and in Sicily, particularly in the Trapani and Agrigento areas. The variant Barbaro is distributed irregularly throughout Italy, while Barbari is very rare and is located in the area between Modena and Bologna.

P. Durante highlights the Greek origin of the name and mentions the case of Santa Vàrvara in the Poro, a locality on the Ionian Sea, where the Greek form Vàrvara was Latinised. For his part, V. Blunda stresses that in Sicilian onomastics the name was preserved especially by liturgical route and through the calendar of saints, which explains its transformation into a surname in that region.