The authors agree that the surname has dialectal roots linked to the term priolu (also recorded as priuri or priuli), related to the figure of the prior. V. Blunda specifies that this word designated the superior of a convent or religious community in the Sicilian ecclesiastical tradition, and suggests that as a surname it could have originated in a nickname applied to someone of grave bearing or linked to domestic service in a conventual house.

F. Miranda distinguishes three independent stocks of origin: a Calabrian one, a Sicilian one and a Venetan one. The first two would derive from the dialect term mentioned, alluding either to the descent of the family of a prior or to a prominent position of the first bearer —such as that of first juror of the medieval city. The Venetan stock, on the other hand, would come from a contracted form of the hypocoristic of the Latin name Petrus: Petriolus, by contraction Priolus, Priolo.

As to its geographic distribution, Miranda notes that the surname is documented mainly in Sicily and Calabria, with a presence also in Piedmont, Lombardy, Lazio, Liguria, Veneto, Molise, Tuscany and Emilia-Romagna. E. Rossoni places the Calabrian nucleus in localities of the Reggio Calabria area, such as Santo Stefano in Aspromonte, Brancaleone, Gioia Tauro and Villa San Giovanni, as well as in Rende.