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A black magic spell used by people from Britain and by rich snobby bastards. The spell works by using it in a sentence to tell people not to do something. This spell is very dangerous. Every time it is used, all the planets in our solar system move 5 miles closer to the sun.
Guy who speaks normally: I'm gonna go fuck my sister.
Guy from London who uses said black magic spell: You must'nt commit incest. It is illegal.
Guy who speaks normally fucking died and the sun devours Mercury.
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Mustn’t Milk Myself March 

Just like in No Nut November, during March, you mustn’t milk yourself for the entire month of March.
Benjamin Dover “Hey, are you participating in Mustn’t Milk Myself March?

mustn't touchit 

You should name your headboard Chris brown because your wall had the shit beat out of it last night, how's your mustn't touchit this morning?

mustn't've 

Contraction of the words must, not, and have. An extension of the common contraction, mustn't. This is an extreme contraction. Please use it with caution.
I mustn't've have taken my car keys with me because I don't have my car keys with me.
mustn't've by BryceM August 11, 2006

Mustn't Masturbate Merry Christmas 

"Mustn't Masturbate Merry Christmas" is a challenge given to mostly men that revolves around that masturbating for all of Christmas Eve and Christmas day. Those who fail are forced to become elves, working in Santa's workshop for the rest of their lives. Those who pass, however, are given 30 minutes to do what they'd like with Mrs Claus, Santa's wife. Most, however, tend to pork her.
Person 1: Why have you been so down recently?
Person 2: I don't know. I just can't find the holiday spirit.
Person 1: Just participate in "Mustn't Masturbate Merry Christmas"!
Person 2: What's that?
Person 1: *shows them Urban Dictionary definition*
Person 2: Don't ever talk to me again.
Person 1: *commits suicide*

Mustn’t Makeup May 

A challenge akin to “No Nut November” except that in the challenge, girls must abstain from using any from of makeup for the entire month of May.
Abby:“Why aren’t you wearing makeup Jess?”
Jess:“Don’t you know! It’s Mustn’t Makeup May Abby!
Mustn’t Makeup May by 69Ligma69 November 7, 2020

Mustn't Masturbate March 

A sequel of sorts to the popular no nutting challenge "No Nut November". Often abbreviated "MMM"
"At the end of Mustn't Masturbate March, my balls are so heavy I can demolish buildings with them
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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
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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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