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The time when you look at a clock and realize that a large portion of time disappeared. It is NEVER 'ninja o'clock', because by the time you've realized the time, it's at least a half-hour after you expected.
Friend 1: "Dude, what the hell happened to the day? I had that interview for that job."

Friend 2: "Ninja-thirty happened, son... remember that 'I'm only going to play a couple games' Madden marathon we just had?"
by Agent 14 December 16, 2009
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