Ass, posterior, concentrating mostly on the anus/rectum. Where the feces (poop) comes out. The Storage area for Feces. Thus a "storage box' for feces.

Shit Box
"After all that tequiila and Hot Sauce I will need to install a new "shit Box"

"So it slipped out of her vagina and before I new it i was up to my balls in her "shit Box".
by Morbog September 27, 2004
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1.A total and complete piece of shit.
2.Basically, a pile of wreckage that the Navy keeps wanting to fly...even though it has more Maintenance hours than Flight hours.
3 See: C-130T
Hey Dave, are you ready to go out and work on that Shit Box 164997?
by Diggs the Mountie November 23, 2006
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What your employer puts your mail and personal belongings in after you've been fired.
I've been told to put your mail, and your files in a shit-box at the front desk. As you already know, Andrea unlocks the elevators at 7:00 AM, so the box will be waiting for you.
by Rupert Pupkin September 07, 2006
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This is what happens to a cunt when a woman wipes her ass in the wrong direction.
Sally rotten crotch wipes forward and her crotch turned into a shit box.
by Nicesta April 10, 2008
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The leaving of fecal matter in a bag or a box, secretly hidden in a small room (especially dorm rooms) as a prank or revenge.
Hey, we shit-boxed Scott. He should smell that in a week or two!
by annonymous April 11, 2005
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