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This stands for “Undies Only Night” this refers to instances in which, due to temperature or mood, it feels right to only wear one’s undergarments during slumber.
“Oh man *strips to undies* it’s an UON fam.”
“Dawg last night was an UON ya feel?”
“UONs are a sacred practice that can, should, will, and are protected by one’s soul.”
UON by #17croissonicsandwhich June 29, 2019
Related Words
Uon • Uonaka • uongoway • uonibla • Uonie • Uonin • uonna • uont too • youon/uon • Yupokit Uonit

youon/uon 

2nd person of 'ion'. A shorter, slang way of saying 'You don't'.
Person 1: "Can I go to sleep? I'm really tired, and-"
Person 2: "Yoooo I'm your friend, youon/uon gotta ask. Ion know who fucked you up, but, like, you really dont have to ask."
youon/uon by lilbigballs August 4, 2023
asking "what's up?" or "what's going on?" sometimes used when someone is mad also.
Joe: what u on bro?
Alex: just chillin dawg, u already know!

Alex: Joe, how u gon' get on my girl like that? what u on??
Joe: That hoe was askin for it folk.
what u on by Joe Weezy May 10, 2006

wat u on 

It means "what are you doing", "what you gonna do today, or later on today. or the rest of the day."
Frank: "Yooo! wat u on tday bro?"
Ramon: "Shit, Just posted, bored af. Y was good?
Frank: "Ha, same lets hit up newport beach tday tho son."
Ramon:"Fasho, Im down, you just gotta drop on tha tank bro"
wat u on by Gizmoe187 April 30, 2013
Mythic Rock disco in Rome during the 70s which sported outragious live events and urban feasts promoted by Tazzuti and his Ritter-Tod und Teufel art productions.
Dai, njamo al Uonna? Si, fammi' entra'! Fammi' imbocca'!
uonna by Thor October 22, 2003
No u backwards, this takes no u to another level
Mega bully: I am the most powerful being in the world! You have a small pp
You: u on
Mega bully: Fucking dies
U on by Mamzmzmskksskzp August 22, 2020
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The phenomenon where adults salivate at children's toys
Every time I walk into the toy aisle, I catch myself kidulting over the latest action figures and LEGO sets!
kidulting by Emotional Cruiser October 12, 2025
Word of the Day on October 4, 2026
British slang for a scientist or technical expert, esp . when the speaker is not certain of the expert’s specific field of study. Not necessarily derogatory, but typically used by persons without a technical background. In the US, the equivalent would be “egghead”, “squint”, or “geek.”

Origin of the word is unknown. Started sometime in World War 2. Given the typical evolution of British slang, could easily have started because what these experts did was confusing or “baffling” to the common person.
According to the boffins downstairs, the murderer used a serrated blade.
Boffin by Agnon February 11, 2023
Word of the Day on October 3, 2026

Pee Calculus

When you have to pee in a movie but don’t want to miss anything, and must do the following mental equation: will the amount I have to pee cause enough discomfort to diminish my attention capacity for the remainder of the movie to an extent which is greater than the amount of the movie I would miss by making a mad dash to the restroom.
I saw Satantango last night, wonderful film but by the 5th hour I had to start doing pee calculus.
Pee Calculus by anorlondo October 1, 2026
Word of the Day on October 2, 2026
Literally "dirty" pronounced with a West Indian accent. Can also have a positive connotation, for example Sean Paul's album title "Dutty Rock".
"The girl is pretty but she corrupt and dutty!"

or, in a positive usage:

"Booya! That freestyle was dutty!"
Dutty by J Hall April 3, 2003
Word of the Day on October 1, 2026
korean word for madam, older woman
Ajumma wait a moment
Ajumma by aintnotinbutnice July 5, 2009
Word of the Day on September 30, 2026
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