not cool man 

when someone does something that is not acceptable, "Not cool man!" is usually an appropriate phrase to inform them that what they did was not nice, cool, funny, or tolerated by society, or just you.

Uncool guy: My butt is so awesome....
Cool guy: Not cool man!

not cool man by Shiraz rocks mannnn February 3, 2018

Not cool man 

a phrase to express deep disapproval, coined by F block H Pre Algebra

That 4.1 and 4.2 test? not cool man.

Not cool man by Qwerty keybord April 10, 2021

Hey man that’s not cool 

What you say when you get caught in 4K kissing your waifu on a pillow

*shines a flashlight*
Sandals: *kissing a pillow* hey man that’s not cool

Hey man that’s not cool by JDMF April 14, 2024

Cheeks 

An Irish phrase meaning shit, derived from ass
(Not to be confused with the literal description of one's buttocks)

"Did you hear the song Aylek$ dropped?"
"Hardly. Her music is absolute cheeks."

"My boyfriend say LaFlame is cheeks."
"Tell your boyfriend I said it's his mixtape that's cheeks."

Cheeks by thecartisan April 26, 2020

sans sheriff 

Lawless use of fonts or typography, with no regard to aesthetics or legibility

I'm putting this CV straight in the bin. Written totally sans sheriff.

sans sheriff by Jamarley July 3, 2019

Breadhead 

Someone who is addicted to obtaining money and building wealth. A money addict and fanatic. Breadheads often work more than one full-time job, and some even participate in illicit activities to "obtain the bread".

A breadhead is like a crackhead, but for money instead of crack.

Breadhead by 🅱️ U S 3 4 8 March 30, 2022

Stink lines

As seen in illustrations or cartoons: Wavy, vertical lines rising above a person, place or thing. Denotes a foul odor.

"You didn't put enough stink lines on your picture of the teacher."

Stink lines by Athene Airheart March 14, 2004