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When a girl gets two periods within the same calendar month. Referenced to "once in a blue moon."
Tom: "Hey, do you want go grab drinks tonight?"

Phil: "I would, but there's a Crimson Star at my house tonight. I got to go to the store to get tampons."
by 2whiteguyz August 04, 2011
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Jul 22 Word of the Day
Short for ultimate bias. Typically used by fangirls and fanboys to describe their favourite celebrity amongst the many that they are fans of.
G-Dragon is my ult
by Uglycat February 19, 2017
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