Late Roman ranks

[Macedon]

Probably the fact that in Greek the word κεντυρίων (kentyrion - centurion) was being used (as stated in my former post) is also evidence that the Latin term survived and was being in broad use. Else, I am pretty sure, they would have transliterated the "new" one(s).

Well, perhaps not necessarily, there are ample examples of Latin words being loaned into Greek which then retains more archaic forms even when barbarisms are affecting "native" Latin speakers in the west. This is particularly true of names (Oularios preserves the non fricative /w/ whereas Latin by then doesn't, Kostas preserves the nasalisations from analogy (/Konstans/, /Valans/), Konstantinos with its vowel length etc.

In terms of official titles you do fine Rex and Princeps (/rigas/, /prinkeps/) etc in Greek and I dare say others probably existed. So Centurio could still be relevant, or it could simply be that Greek is being conservative with these terms.

This is one of those areas which are seriously lacking in attention.

I of course agree that there can be no certainty, but the word centurion is not standard Greek (with it I mean it is relatively rare as a term) and is only marginally used when compared to the respective proper Greek words (taxiarchos, ekatontarchos/es etc). I think that were it not in use in proper military jargon, it would not be used at all. I would be much more uncertain if it was the predominant term used, for then chances for it to have been a Greek conservatism would surely be much more probable.