Alternative name for penis, usually used amongst males or as a joke.
Hey Matt you took a long time in the washroom, were you tampering with your release valve or something?

Friend 1:What took you so long to get here?

Friend 2: Sorry, I was stressed after a long day of work and, don't tell anyone but I had to pull my Pressure Release Valve
by LessOffensive September 21, 2009
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