E. Rossoni notes that Maragni has a scattered presence in the Mantua area. Its variant Maragno, by contrast, shows several independent clusters of origin (ceppi): one in Veneto, with cores in the Padua and Rovigo areas; another in the Ferrara area; one in the area between Rome and that of Latina —possibly also of Venetan origin—; and another in the strip between the Matera and Taranto areas. Rossoni proposes that both forms would derive from the medieval name Maranius, of which a documentary testimony exists relating to the year 369. He further mentions the 17th-century writer known as Maranius Anianus.

F. De Laurentiis offers a different reading: he considers that the surname results from the combination of the personal names Mara and Agnello, this last understood mainly as a symbol of Christ, of his sacrifice for humanity, and also of purity and Christian fidelity. Within that framework, the surname could take on the meaning of "fidelity afflicted by events or by people".