A mean penis, specifically a penis that is holding out which would be a mean thing to do. Also includes people who happen to have penises that are exceptionally mean.
Snexys was quite irate to find that Chris would not do her. She informed him that he was being a mean penis, to which Locked called him a meanis. As snexys and locked walked away to go be naughty in front of Grant instead of Chris, Chris cried himself to sleep for he was now more useless in bed than a seemingly gay foreigner.