1. Phenomenon when, after blowing your nose into a tissue, you sense the distinct feeling of the booger dislodging from nose but fail to find the booger in the tissue. Then, after some passage of time, the booger is discovered on a part of your shirt that seems physically impossible.
2. Rarer phenomenon when the booger winds up on another individuals shirt due to proximity when blowing the nose.
3. A person who regularly displays boogers on their shirt as described in #1.
Johnson: My sales numbers this quarter surpassed budget again!
Boss: Johnson, what in the heck is that on your shirt collar?
Johnson: Huh? Aha, that's where he landed! It's just my shirt booger.
Boss: Ok, but what about the one on your shirtsleeve? Is that another shirt booger?
Boss: Johnson, your booger surpassed the tissue again, you're such a shirt booger!