E. Rossoni proposes that the surname derives from a nickname based on the archaic Venetian dialectal term cavria, the name of an instrument used to lower and hoist the masts of sailing boats, especially useful for crossing stretches of river with low bridges. According to this interpretation, the first bearers of the surname would have dedicated themselves to that type of river manoeuvre. Rossoni places the origins of the surname in the Ferrara area and the Rovigo area, with specific presence in localities such as Stienta and Occhiobello.

F. De Laurentiis offers a different reading: the surname would refer to the root cabra —with the variant cavra, peculiar to northern Italy— and to its derivatives, such as capraio (in the north, cavraro or cavrero), with the sense of "enclosure or covered shelter for goats". This base could correspond both to a nickname or trade name and to a place name. De Laurentiis agrees in noting the Po Valley areas of Mantua, Rovigo and Ferrara as the area of rooting of the surname.

Both authors converge on the geography: the strip between Mantua, Rovigo and Ferrara appears as the reference territory, although they differ in the original motivation of the name, between a river nautical instrument and a root linked to the raising or housing of goats.