A very large penis about 1 foot 6 inches long and of varying girth. Said penis must be large enough to cause discomfort to a recipient in any act of sexual activity.
Daniel: Hey man, I gave THIS 18 inches of pain last night! She was screaming for mercy!
Duncan: I wish mine was 18 inches, all i have is this 1 incher...
by 18Inchwang June 22, 2006
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