A residual, hard piece of fecal matter that remains lodged in the rectum after taking a dump. It causes severe itching, but rarely pain. The only remedy is to dump again or remove it with a finger.
I took a dump after eating peanuts and I had an irritaint that I couldn't reach until I got in up to the third knuckle. If you are wondering, yes, it was a peanut.
by coyotemutt November 11, 2011
When your underwear constantly rides up and you have to pick it out. This indecent usually coincides with "swamp ass".
I was irritainting for the last hour of my hike yesterday. Every twenty minutes I had to pick my underwear out of my ass.
by jonnesovic April 23, 2011