I don't know Japanese, but I believe the furigana indicates it's to be pronounced Rondo. I didn't know that was a musical term until a few years ago; I always just thought Konami chose it as a cool alternative to the word Circle.
I see, that may be the case, didn’t think about that
update:
In fact yes, i went for a closeup look at the title in the Cover, between the characters 輪 and 廻 actually theres a kana translation as ロンド, never noticed that before ahaha, how silly of me.
Yet is funny to notice how magazines and even the japanese guidebook translates it more literally as Reincarnation
IMG
(http://www.vgmuseum.com/mrp/cv-rob/scans/Minolta394.jpg)
(https://vignette.wikia.nocookie.net/castlevania/images/6/6b/RoB_Official_Guide_Book.jpg/revision/latest?cb=20091226112827)
I think i kind of prefer it over Rondo tbh
MegaDriveFAN Jun 1993 issue (published in May):
(https://vignette.wikia.nocookie.net/castlevania/images/5/5a/MegaDriveFAN_Jun_1993-P053_%281%29.jpg/revision/latest?cb=20140326051324)
From the upper section:
"This is an action game from a new series about vampires."
From the lower section:
"When talking about a game about the vampire Dracula, "Akumajou Dracula" from the same company comes to mind. However, "Vampire Killer" is not a sequel. This game is developed as a completely new project with maintains the basic system and atmosphere (of the Castlevania series). "