this is the title of a song by a very popular Japanese rock band called “L’Arc~en~Ciel“.
yeup, it’s translated as “the arc in the sky” or “the rainbow” in French.
The band, pronounced as raruku an shieru (ラルク アン シエル) was formed since 1991, currently consisting of 4 band members; hyde, tetsu, ken and yukihiro.

i came to know of them through Animes show/movies as most of their songs are used as either the opening or closing songs. but i wasn’t as interested as i am with Orange Range.
this change when i saw their latest album Kiss.
nope, didn’t buy that album. instead, i opted for their Best of 1998-2000 Compilation album (a good way to know one band’s genre).
having listened to it, i fell in love with “Dive to Blue”, “Honey“, “Snow Drop“, and “Forbidden Lover“. they’re a must-listen-to songs. wonderful music arrangements.
[L'arc-en-ciel -"Dive to Blue"]
they just wrapped up their 2008 Tour in June and will be on hiatus (for live shows) until 2011.
i don’t have much yet, but if you’re interested to know, here’s some of the links that offers more info on the Band:-