A. Bongioanni considers that this surname derives from a given name of Persian origin, and finds it arbitrary to interpret it as if it were Greek, in particular as derived from the term kyrios ("lord"). Among the saints who bore this name, he highlights especially Saint Cyrus of Alexandria, a martyr in the year 311, whose feast is celebrated on 31 January and who is venerated as the patron of physicians. He also notes that in some localities, such as Genoa and Pavia, the name Ciro is confused with Siro.

V. Blunda, on the other hand, proposes a Greek origin and derives it from the term cỳros, a form preserved in the onomastic tradition of the Mediterranean since ancient times. He links this name to the lexical sphere of Byzantine courtesy by its phonetic proximity to kyrios, a Greek word that designates the lord. Blunda places it within one same onomastic group together with parallel forms such as Cirio, Cirelli and Cirillo.

Both sources agree that the starting point of the surname is a given name, although they differ as to its language of origin: while Bongioanni defends the Persian origin and rejects the Greek interpretation, Blunda maintains precisely that Hellenic reading.