The name "Octavian"

[SOCL]

Thanks for clarifying. My main point was that, if as you say, Cicero did not know "Octavius" before he became "Ceasar" why would he ever use the name "Octavius"? Or are you claiming that he kept "Octavius" even after adoption? Or that Cicero was using his earlier name to demean him?

Cicero would likely have found out Octavian's family background and other such information after the adoption. I'm not claiming Octavian kept the name Octavius after the adoption - quite the contrary. Cicero refers to Octavian as both "Octavius" and "Caesar" - I don't think we should read much into why he chose one name here or another name there.