The authors agree that the surname has an anthroponymic origin, derived from the name Gervaso or Gervasio, of Germanic root: composed of gair, "spear", and the Celtic element vas, "servant".

E. Rossoni notes that the surname could also derive from place names linked to the same saint, such as Capriate S. Gervasio, San Gervasio d'Adda —both in the Bergamo area— or San Gervasio Bresciano, in the Brescia area, although he does not rule out that it comes directly from the personal name. Rossoni adds that the surname is typical of the Bergamo area, with a greater diffusion in the Valle Brembana, and that the cult of Saint Gervasius had relevance in the region of Lombardy: according to tradition, the two martyr saints —Gervasius and Protasius— were buried in the basilica of Sant'Ambrogio in Milan.