Well, there goes the neighborhood. I already listed some people who would have cared back in the day, though. Anyway, why do you care that I care?
It's a good thing we're here to assure you that this is not the case! p.s. aren't you glad somebody cares?The only reason I'm arguing this point is because I had the exact opposite confusion -- my initial impression from the titles was that Castlevania: Dracula X was a completely original game that had nothing to do with the PC Engine CD game, other than being in the same series.
Rondo is borrowed from French, actually (and they use some kind of German at the introductory cutscene on the PCE CD).And for what it's worth, "Rondo" is an English word, and isn't part of the title of the SNES game in any territory.
Now you're just messing with me, right? Castlevania: Dracula X. The subtitle is the part after the colon.
Thought you meant the PCE game, which is obvious if you note that I mention that game's subtitle specifically (I didn't hallucinate it on the SNES game's box). No, I have more entertaining things to do than mess with you, no worries there.
On the subtitle front, many of the game in Japan had the exact same title as the NES Castlevania's Japanese version, which certainly would bear out your earlier assumption that the game isn't related at all to the PCE game.
I have no idea why all this is worth discussing either, but one last thing: On the JPN title, you note that Akumajo Dracula is the series name, but "Castlevania X" would be silly - so they chopped up the JPN series title for "Dracula X." This is why I find it hard to call "Dracula X" a subtitle, though indeed it may be called one. Another example of the necessarily rather fragmented marketing Konami has employed for the series throughout its run.