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When a human male stands erect to urinate only to find two entirely separate streams of urine cascading out of one's length.

Often caused by having had a quick tug mere moments previous, this phenomena can result in a good deal of said yellow beam to fall upon your jeans/shoes/carpet.

Once the bi-stream begins, there is absolutely nothing one can do but to hope and pray that both streams fall within the toilet bowl or floor, where the buck can easily be passed.
I tried in vain to hide the bi-stream that afflicted me whilst in a particularly well-lit pub on a first date.
by English Nuclear Power July 31, 2009
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