Within Minecraft, this is an alternate name for a "creeper", so-called because it looks like a penis (a green one) and it explodes when it gets close to you.
Watch out, exploding penis to your left!
by TheSophera December 05, 2010
A rare condition where the penis tares open when the blood filled cavities in it rupture. Usually caused by having sex constantly over a very long time. Said to have happened to Chuck Negron of three dog night.
An exploding penis is rare.
by Deep blue 2012 February 09, 2010