look up any word, like sex:
Used to describe a load so epically massive that one's sphincter clamps shut in an attempt to block its passage. Ultimately, this fails and just when you try to force it out, your sphincter surrenders to the inevitable. The enormous girth combined with the force exerted results in a painful (and sometimes audible) ripping sensation.

The sphincter learns from this experience and will clamp shut even tighter the next time. There are unconfirmed reports of microscopic diamonds being formed from the intense pressure.

The most astounding characteristic of the sphincterror is the complete loss of any will to brag about or display the result of this "achievement."
girl: you were in there a long time. Do you feel better?

guy: lips quiver in an attempt to speak

girl: oh no! Tell me it wasn't a sphincterror!!!
by twilyth September 23, 2009