Top definition
An unidentified butt object
Jonathan " My butt feels weird"
David "I think you might have an UBO, might want to get that checked out"
by strugglepig May 27, 2017
Get the mug
Get a UBO mug for your cousin Zora.
Unhealthy Boy Obsession Syndrome

When you just happen to know everything about a boy that there is to know. Their address, their age, hobbies, grades, personality, what their house looks like on the inside, their families names, you stalk their social networking sites to the point where they will find out eventually even if there is no legitimate evidence you were on their page.

Some results of this could be bad like them thinking you are a creepy stalker, or a freak that will never get a boyfriend.
Girl: "Man, I've got such a bad case of UBOS, he's so gorgeous!"

Boy: "Holy shit take that UBOS to some other guy you freak!"
by CanOfBread February 27, 2011
Get the mug
Get a UBOS mug for your papa José.
Useless Bag of Skin zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
Andy was a UBOS.
A loser. A worthless person.
by Frankie Alvert February 07, 2005
Get the mug
Get a ubos mug for your sister-in-law Sarah.
buy the domain for your pet vlog