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Mastering Chemistry 

A website created to make the lives of American college students a nightmare through the use of nazi-like grading on significant figures and rounding throughout 15+ pages of hell. Commonly referred to as a bitch for changing 1 number in each person's given values to piss people off.
"Hey have you done the Mastering Chemistry for this week yet?"

"No but I heard it's a real killer."

"Yeah I tried the hints and couldn't even work through those!"
Mastering Chemistry by CHE108 May 15, 2012

chemistry class 

its not a science class, in fact chemistry class is fucking math. I didn't fucking sign up for fucking math
student 1- man fuck my life
student 2-why
student 1-chemistry class
student 2-is it really that bad
student 1-. 1.00 km (1000 m / 1 km)( 100 cm / 1 m)(1 inch / 2.54 cm) = 3.94 x 104
or 39,400 inches
student 2-the fuck is that
student 1-hell
chemistry class by it cant be September 29, 2020

Chemistrating 

John and Tina are chemistrating in the lab.
Chemistrating by Jons1287 February 21, 2011

organic chemistry 

A class that rapes the shit out of you and your GPA. Learn useful things like deprotonating your mom and what not to do after college
The organic chemistry did me in the butt and I bent over for it.
organic chemistry by Kbad December 6, 2006

Friends with chemistry

Friends who are sexually attracted to one another, but maintain zipper discipline.
Friends with benefits? Nah, Cathy's already got a boyfriend. We're more like friends with chemistry.

altered my brain chemistry

movie, song, a piece of art or something else that changed you drastically, made you basically a new person or heavily influenced the way you perceive world around you, other people etc.
This song altered my brain chemistry, I basically became someone else after listening to it!
More from Urban Dictionary
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
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).
After we broke up, he was floxi to me.
floxi by Dr. Geek May 13, 2009
Word of the Day on September 28, 2026
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