When you do everything sexual (for example: got sucked off, etc) but you didn't actually had any sex.
Kyle: So yesterday Kara sucked me off. It was totally great.
Chad: Dude you and Kara have been together for more than a year and still haven't had sex.
Kyle: Yeah I know, I'm totally getting blue balled.
Chad: It's called a virgin rainbow dude.
A girl that dyes her hair different colors, you assume the carpet match the curtains.
Look at the honey, she definitely has a rainbow bush.
When a person uses every color of chip two times on one raise during a game of poker; mostly in Texas Hold 'Em.
Oh my god... Double Rainbow Raise... Double Rainbow Raise all the way across the table...
A homosexual man, especially effeminate that is rather stupid.
Bravis: Since we can’t call them f*gs anymore, I’ll make a new slur
Selden: What
Bravis: Rainbow Wanker
Selden: Let’s add it to Urban Dictionary!
Some motherfucker who was given a small amount of power who then uses it to go on petty power-trips.
A: Yo, did you see Michael deleted all the political posts in #news?
K: Yeah, he's a real Rainbow Ranger.