The consulted works concur in tracing the surname Moroni to a common etymological base. It derives from the medieval personal name or byname Moro, itself drawn from the Latin Maurus, which originally designated the inhabitants of Mauritania in northern Africa. Over time, the term shifted from a strictly ethnic meaning to a descriptive one, referring to people of dark hair or brown complexion, and in some medieval contexts it also came to denote the so-called Saracens. It is recorded that the surname belongs to a broad onomastic family built on the moro / Maurus root, which generated numerous parallel forms in medieval Italy, including Moro, Mora, Moretti, Morelli, Mori, and Morone.

E. Rossoni specifies that within this family Moroni functions as a patronymic or collective form, carrying the sense of "the Moro" or "descendants of Moro." Rossoni also notes a possible toponymic origin in certain cases, linked to localities containing this element, such as Pieve Porto Morone or Pratomorone; in those instances the surname would identify people coming from those places rather than bearers of a personal nickname. Geographically, Rossoni observes that the surname is distributed across central and northern Italy.