1. The act of releasing urine from your penis.

2. The act of releasing semen from your penis
I drained the main vain all over her.

Well, time to drain the main vain
by Nttm May 12, 2010
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as in you need to go urinate(av a piss).
B: aw ive drunk too much. coming to drain the main vain?
C: yer sure...
by gareth matthews January 28, 2007
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