The authors agree that this surname is of toponymic origin and derives from the place name Bassano, present in several localities of northeastern and central Italy, among them Bassano del Grappa (province of Vicenza), Bassano Bresciano (province of Brescia) and San Bassano (province of Cremona). Its main diffusion is concentrated in the Veneto and in Lombardy.

A. Bongioanni and E. De Felice agree in noting that the surname can also derive from the old personal name Bassano, spread in Lombardy through the cult of Saint Bassano, patron of Lodi. This saint, born in Sicily, was bishop of that diocese and died in the year 413; his name was little known outside that sphere. Both authors also indicate that, in relation to the old Jewish community of Bassano del Grappa, the surname —as well as the variant Bassani— is also in use among families of that tradition, deriving in that case directly from the name of that city. Bongioanni adds that the preferable base form is Bassiano, which continues the Latin Bassus.

E. De Stefani adds that the surname is documented in Friuli from the end of the 16th century, and that as a personal name it is attested in that region as early as the 15th century. He also notes the existence of surnames derived from the same base in the Vicenza and Lombard area, such as Bressanelli in Sellero (province of Brescia).