The surname Odoardi (and related forms such as Odoardo) is of anthroponymic origin, derived from the medieval Latin name Odoardus, itself of Germanic root. E. Rossoni documents its presence as early as the 13th century, linking it to the Germanic onomastic tradition that spread throughout medieval Italy and eventually became a surname.

V. Blunda traces the etymology more precisely to the Germanic compound Othal Hardu, carrying the meaning "strong through nobility" or "valiant of noble lineage" — elements pointing to nobility and strength. Blunda also notes its relation to other names sharing the same root, such as Eduardo, placing Odoardi within a broader set of Germanic names that circulated across Europe before becoming fixed as surnames. For its part, it is recorded in Surnames in Italy that the name derives from the German first name Edoardo, interpreted as "guardian of the property," a gloss that reflects a parallel etymological tradition for this family of names.

Geographically, the form Odoardi is found primarily in the areas of Pescara and Teramo, in Abruzzo, with an additional presence in Rome, while the form Odoardo is associated with Veneto and the Ligurian-Piedmontese area.