The authors agree that this surname derives from the biblical name Giobbe (Job), whose root is the Hebrew haijob, meaning "enemy" or "the one persecuted", taken into Latin as Hiob. It is a name that became a surname late and with limited diffusion.

E. De Stefani notes that in Italy there are churches dedicated to San Giobbe in Venice and in Bologna, and that this saint is also the patron of the weavers of Lombardy. He stresses that the Friulian form of the name is Jop or Job, and that the surname is documented in Illegio —a hamlet of Tolmezzo, in Carnia, the mountainous area of northern Friuli, in the province of Udine— from the end of the 15th century, with a presence also in Gemona and Cervignano.

E. Rossoni links the surname with the medieval form Ioppo, derived from the Hebrew Giobbe, of which he records an example around 1600 in Postalesio, in the Sondrio area. He adds that Iob and Yob are surnames of Jewish tradition proper to the Val di Non, and that the surname has a main cluster in the Udine area —with a presence in Tolmezzo, Tarcento and Gemona del Friuli— and another in Trentino, especially in Cunevo.