Emidio is of Latin origin, meaning 'rival'. It is derived from the Roman family name Aemilius, which was thought to be based on the Latin word 'aemulus', meaning 'to strive for' or 'to rival'. This name gained popularity during the Middle Ages and has since been used in various forms across Europe. The Italian form of this name is Emidio, while its Portuguese equivalent is Emilio.
The name Emidio experienced fluctuations in popularity over the years, with a peak of 21 births in 1924. However, it became less common after the 1930s, with six or fewer births per year from 1951 onwards.