The consulted works concur in deriving this surname from the occupational term massaro (also massàio in Tuscany), which served as both a nickname and a general appellative, and in Sicily as a title of respect. Its meaning varied according to period and region: in northern Italy it referred to a "settler" or "sharecropper," while in central and southern Italy it also covered the senses of "bailiff," "steward of rural estates," and "head of agricultural and stock-raising enterprises." It is also recorded, more simply, as the term for an owner of lands and farms.

E. De Felice notes that the surname is found throughout Italy and that several of its variants show specific geographical distributions: Massarino and Massardo predominate in Liguria; Ammassari in Apulia and in the Salento area — the southernmost part of the Apulia region, in southern Italy —; and the forms Massarìn and Massarutto in Veneto.