Fist Up 

To push one's fist right into another's asshole. This is also called an JAM UP. Normally used in times of extreme agressiveness. Males in particular detest this as it enlarges the rectal passage by up to six times.

A: Did you see Tom yesterday?
B: No, he skipped school to miss the maths test.
A: I could give him a fucking fist up.
B: Here, let me give you one, you foulmouthed bastard.
A: MOM?!?! NO NO NO! AAAAAAAAAAAAARGH!!!

Fist Up by Mr. Knowall September 2, 2010

Right fist up in the air 

A way of showing Black Power without shouting it.

Yo we don't need to shout black power. When the Labor Day Parade happen again, just put your Right fist up in the air; they'll know what time it is.

Right fist up in the air by Jay89Jay91 March 20, 2018

wanna back that up with a fist 

sumthing u say to a douche who is talkin shit and cant back it up, a.k.a 7-2

gay wanna back that up with a fist ill stab u wench ahhh im sorry

wanna back that up with a fist by Anonymous May 22, 2003

Upside-down Fist Bump 

The act of a regular fist bump, yet the fist is upside-down. This kind of fist bump is a rejection of the purpose of the fist bump, yet must be done for the purpose to fit in.

Ted: Dude, I just totally busted that wimp in the face
Victim's Friend: Oh, yeah man
Ted: (Requests a fist bump)
Victim's Friend: (Uses an Upside-Down Fist Bump)

Upside-down Fist Bump by LexxiFoxxx June 8, 2011

fistup 

Idk what it means, Rowan Atkinson(Mr. Bean) said it in a comedy bit called Dirty Names

Answer your names-- Anus, ass bandit, bottom, clitoris, where are you clitoris...doodoo, enema, fistup--- c'mon, grow up, please!! Genital

fistup by MystiqOfTheWind May 31, 2021