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umop apisdn 

= "Upside down.": Read Upside down, and backwards.
Try using Ctrl+Alt+Arrow-Down
Do you know Jack Johnson? He wrote this song: "umop apisdn".
umop apisdn by MopfMore April 2, 2015
Related Words
A type of ammo for tanks, full name is Armour-Piercing-Fin-Stabilized-Discarding-Sabot
Tank Commander to the loader - Load the APFSDS
Tank Loader - Yes sir!
APFSDS by BiggityBoy21 October 3, 2018
i was driving down the street and talking on my phone ATSDT
ATSDT by MZ Platinum March 20, 2012

umop apisdn 

umop apisdn
umop apisdn by Anonymous August 25, 2003
Word of the Day on March 22, 2015
The school district of Averill Park, New York where students can scream the N-Word and not get in trouble. Here, you will see fifteen-year-olds making bank by growing their own cannabis in the woods.
If the APCSD cooking ladies don't have that speedbag arm fat, you know your lunchtime munchies will be ruined by shitty food!
APCSD by coffee_by_the_pot June 8, 2021
What does aptdkm mean? Well it means this: a=a P=person t=that d=doesn’t k=know m=math
Aptdkm is in this classroom XD What a loser. She doesn’t even do math. If I was her I would do it all cause then I would have no work to do during the school year and home.
aptdkm by C00LkExpert February 6, 2018
More from Urban Dictionary
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

Slop Grenade

When someone uses AI to generate a large document, slide deck, or piece of code/software and tosses it over the fence for you to deal with.
Chad: Hey Brent I sent you the new backend API change to review, it’s only 100 files changed.

Brent: he just tossed me a slop grenade
Slop Grenade by Joe Squid September 28, 2026
Word of the Day on September 29, 2026
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