F. Miranda notes that this surname derives from the medieval personal name Susanna, an Italianization of the Hebrew biblical name Shoshannah, meaning "lily", a symbol of purity and beauty. Miranda also points to a possible older root: the name would have been recorded on a sarcophagus of the year 2000 BC and would come from the Egyptian root SŠN, meaning "lotus". Both Bongioanni and Miranda agree, in any case, on the meaning "lily" associated with the Hebrew.

A. Bongioanni highlights the link of the name with Saint Susanna, a 4th-century martyr whose feast is celebrated on 18 January, and mentions the historical existence of the derived form De Susanis, a surname typical of Udine, in the Friuli-Venezia Giulia region, today extinct.

Miranda considers that it is probably a matronymic surname, that is, derived from the name of the first woman who bore it. As for its distribution, the surname is documented in zones of central-northern Italy —Veneto, Lazio, Friuli-Venezia Giulia, Lombardy, Tuscany and Piedmont— although it also appears in regions of the south: Apulia, Sardinia and Calabria. In Sicily its presence is limited to the Messina area —specifically Rometta— and to the Enna area —specifically Centuripe. Miranda recalls, in addition, that Susanna is the name of two biblical figures: in the Old Testament, a woman falsely accused of adultery and saved by Daniel; in the New Testament, one of the disciples of Jesus who brings the myrrh to the sepulchre.