An acronym referring to Uncontrollable Boner Disease. Victims are subject to getting a boner from pretty much everything, including (but not limited to) head pats, colorful lights, the smell of delicious food, or watching tv.
Guy 1: "Hey man, why weren't you at Todd's party last weekend?"
Guy 2: "I was getting emergency surgery to treat my Type IV UBD."
Guy 2: "I was getting emergency surgery to treat my Type IV UBD."
by chunsberger October 04, 2011