Selling Yourself Short 

Not reaching one's full potential. The origin of the term is "short selling" a stock (i.e., betting against a company). The "short seller" essentially "borrows" stock from a company and agrees to pay back the company whatever the stock is worth at some point in the future. The purchaser sells the stock immediately, anticipating that the price will fall over the next few months. If the stock price actually falls, the purchaser will pay back the company less money than what the purchaser sold the stock for.

Jane: "I'm not good at science classes."
John: "I think your selling yourself short."

Jane: "Want to see a movie tonight?"
John: "Let's not sell ourselves short here. I heard Warren G is putting on a concert in Williamsburg."

Selling Yourself Short by ZeekZeek November 13, 2009

jerb 

well known from south park
rednecks get angrry that future folk took there jobs so they yell
They took ouare jerbs!

Them future folk took ouare jerbs!

jerb by Jimberley Kim April 7, 2005

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

schmegegge 

Yiddish slang word meaning bullshit, baloney, hogwash, nonsense, crock of shit or hot air.

I don't buy the schmegegge about Morty sleeping with Moira.
His version of the story was pure schmegegge.
The whole schmegegge was made up to get Liz a little bit of attention.

schmegegge by budsbabe February 1, 2008