1 definition by Baby S. Doll

To throw up profusely, normally in the figurative sense. Usually in response to something that is too cute or just outrageous for words. Done in the fashion of the King of Cosmos from Katamari Damacy in which the person emits a large rainbow from the mouth that has pink instead of indigo for some reason.
My girlfriend is so cute, she makes me want to Royal Rainbow whenever I see her. It must be love.
by Baby S. Doll July 27, 2007
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