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The act of a "once presumed straight" person , who has recently come out as LGBT and become more comfortable with themselves, becoming REALLY gay, REALLY fast.
"Hey, what's with Tom? Last semester he was wearing sweatpants and dirty t-shirts. Now he's got frosted hair, tight clothes and pride bracelets on".

"Yeah, he performed a rainbow rush to make up for all those years in the closet"
by mattyj94 July 29, 2015
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