The authors agree that this surname derives from the Germanic personal name Emma, originated as an abbreviated or hypocoristic form of compound names. A. Bongioanni notes that the root imme means "laborious and diligent" or, according to the linguist Förstemann, that the initial element corresponds to Irmin. E. Rossoni specifies that the form Emma comes from an apocope of Germanic names with the element ERM (such as Ermingard), whose original root is ERMIN, the name of the demigod that gave its denomination to the tribe of the Herminones according to Tacitus; the intermediate r was lost over time, a frequent phenomenon in the diminutive forms of Germanic onomastics. V. Blunda adds that the root irmin can be interpreted as "universal, vast, all-encompassing".

Bongioanni mentions Saint Emma, founder of convents in Carinthia in the 11th century, whose feast is celebrated on 29 June. Blunda, for his part, highlights Emma of Normandy (~985-1052), daughter of Duke Richard I, queen of England as the successive wife of Æthelred II and of Canute the Great, and mother of Edward the Confessor and Harthacnut. The variant D'Emma reflects, according to Blunda, the integration of the anthroponym into the patronymic system of southern Italy.