look up any word, like ratchet:
 
1.
UPI
Un-Identified Party Injury, Mysterious injuries discovered after a a period of intoxication.
This morning, I woke up with a UPI on my leg.
by McBain February 07, 2002
 
2.
upi
a word used in instant messaging when you accidently have your right hand fingers off by one on the home row on a qwerty keyboard.
you're

becomes

upi
re
by sirtalksalot June 05, 2009
 
3.
Unidentifiable Party Injury

Upon waking from a night of partying, you find one perhaps two bumbs, bruises, scratches, or bites and are not completely certain of there origin
Partygoer#1: Wow!! What the hell happened last? I am riddled with U.P.I
by JoD CoD October 14, 2008
 
4.
Literally: U packin it?
to ask someone to pack paraphenalia with marijuana
yo you got weed? u.p.i?

Person A: yo u.p.i?
Person B: yo u.p.i
Person A: nah i only got a bowlsworth upi

by Jim Wayne June 08, 2006
 
5.
Upi
An indian girl who moved to the u.s.
She thinks she is ugly but in reality she is very pretty.
She likes wanna-be gangstaas and black people and likes it when people mistake her for mexican c;
Black Man- Yo dawg, who is that mexican girl?
White Man- You mean Upi? She's not mexican...shes indian
Black Man- Ahh...well she's hot
by noahc; November 26, 2010