Dario is the Italian and Spanish form of Darius, the name of the great Persian kings, which comes from the Old Persian Darayavahush and means "possessing goodness" or "holding firm the good". The Italian playwright Dario Fo, winner of the Nobel Prize in Literature, is its best-known modern bearer. In the United States Dario has been in the top 1000 since 2000, when it ranked number 806; it reached number 639 in 2024 and stands at number 760 in 2025.