Unidentified Drinking Injury - A mysterious injury received during a bender (qv) and of which the victim has no recollection
"Honestly Officer, Me and my brother N-Lew don't know WHAT happened. We was just heading back from the Tav with these 2 georgous chicks and when we woke up they'd turned into Swamp Donkeys!" said J-Lew. "Must have been some sort of U.D.I." N-Lew added
Stands for Unidentified (or Unknown) Drinking Injury. Any kind of injury that is impossible to explain due to the fact that the injury occurred while drunk or otherwise in a wasted state.
When I woke up the next morning, there was an abundance of U.D.I.'s: scrapes, bruises, open flesh wounds -- I thought to myself, "I don't remember walking through a swamp or viciously attacking a laundry hamper."