The weight of ones penis.
Fiona: Jerry, how much do you weigh?

Jerry: 10 stone... Hold on are we including cock weight?

If so 15.

Fiona: Jerry, you have a hefty penis.
by Xavier Duck December 28, 2012
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the excuse given by those accused of being overweight, implying their excess weight can be attributed to a large and heavy schlong.
"mate you're a fat shit"
"nah dude its all cock weight
by Glavič1 March 21, 2011
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