When you take a leak in an urban environment. E.g. in a telephone box, in a doorway or on a car. Usually coincides with alcohol consumption. As your level of intoxication increases, the locations of your urban pisses become more and more antisocial.

Sometimes shortened to just 'urban', when used in a context where the meaning is obvious.
"I was drunk as we were walking into town, so I had to have an urban piss behind the bins."

"On the way back from the club I was so lashed that I got it out and had an urban piss right there on the pavement."

"I might just go for a cheeky urban you get me?"
by otleybey April 28, 2010
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A battle between contemporaries, as to who has submitted the most Urban Dictionary entries.
CPiz: "I now have 6 Urban Dictionary entries to your 4"
DGiz: "I guess you're winning the Urban pissing contest then"
CPiz: "Yes, aren't I clever!"
DGiz: "Eat a dick"
by ThePonderer December 6, 2016
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