These surnames, like Esposito, derive from the surname granted, in central and southern Italy, to abandoned children (foundlings). Proietti derives from the Latin word proiectus, from the verb proicere ("to set down, to throw, to abandon"), a term that gave its name to the institution known as Rota Proiecti, a wheel or retractable cabinet of anonymous use where the newborn was deposited. This surname is documented by De Felice as one of the surnames given to abandoned children and presents its greatest frequency in Lazio, especially in Rome, and in Umbria, reflecting institutional practices proper to central Italy. The related variant is Proietto.