The surname Pacca shows an uncertain origin, with different hypotheses proposed by the authors. In this sense, E. Rossoni suggests that it could derive from a nickname or medieval name based on the Lombard term pakka ("salted meat"), possibly linked to activities related to the supply of provisions, which would indicate an occupational origin.

For his part, V. Blunda proposes an alternative interpretation of Germanic root, relating it with the Lombard anthroponym Baga, of disputed etymology, and notes that the current form could be due to phonetic processes proper to the evolution of the name. He also expressly rules out its link with the Italian pacca ("slap"), considering it a folk etymology without foundation. In this way, the surname could reflect both a nickname and an anthroponymic origin, without a single definitive interpretation.