If you want a name that actually sounds like a name and not a word, call him Crono.
They both sound exactly the same (the H in Chrono is silent and doesn't effect pronunciation). Most names are words (to get technical all of them are).
(Oh, I'd recommend calling Frog "Glenn", by the way. I just think it makes more sense... Your choice, though)
Kaeru FTW!! But really, I think calling him Glenn only makes sense once he's laid Cyrus' ghost to rest and finally reclaimed his name. I could also see making a case for right after he first regains the Masamune, after he opens the cave to Magus' castle, but you don't get access to the renaming Nu (Numingway! >_>) that early, so...
"Maou" (Janus's Japanese name) means, according to the translators, "Dark King" or "Witch King". "Magus" is a title, not a name...His name is not Magus, it's Janus.
Like previously stated by me in this post, words are often used as names. Just like how Kaeru means both Frog & Change, but it's also his name. Maou is his name at that time. We don't know the exact circumstances for the name change, but I think it more than made sense for him to change his name...or at least it was understandable...
I'd go for either Maou or Gil for renames in Magus' case. Maou would make sense since that's who the party knows him as and he really has no reason to change for them. Then again, it is part of his past life, so I could see him already change his name to Gil as a way of starting over, but I think now with the new ending, such would probably occur post-game.
