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1.
To drop one's pants while standing drinking at a bar without calling attention to yourself. (Originated at The Rail Pub in Savannah, GA)
A group of friends walk into a bar and start drinking, in the middle of their drinking, they start dropping their pants one by one without telling enyone. People start noticing this around them, but they act as if nothing out of the ordinary is happening. That is what we call Rail pants
by Some Dude from Savannah November 22, 2006