The day after Hump-day. AKA -Thursday. The day Friday in itself is a holiday celebrated by many people around the world on a weekly basis. Friday is also a state of mind and Friday Jr is an extension of the holiday and that state of mind.
Justin: "God I cant wait for this week to be over! The boss has been riding my balls all week and its only Wednesday!"

Mike: "Well at least tomorrow is Friday Jr.! The weekend is in sight!"

Justin: For shizz!
by Captain B.C. April 18, 2010
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Thursday...When the weekend drinking begins.
Its Friday Jr. pal.....man up were heading to the bars
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