mfn 

Magic Fucking Number.

The Maintenance Dept receives a call from production..

Production: This machine isn't working properly watch this.

The production operator hits a button and it starts magically fucking works.

Maintenance man: Another MFN.

Production operator: But this machine messed up 7 times.

Maintenance man: Oh, don't mind me, this is just another one of those cases where it runs right when you call me. 8th try's the c harm---talk about a magic fucking number.

mfn by Simplistikk July 17, 2010

MFN 

Stands for Mother Fucking Newbie.

Bob: "Hey, how's the new guy working out?"
Phil: "Just like all the other MFNs we have around here!"

MFN by PicPrison December 25, 2007

Mfn 

My-forever Nigga

Even if y’all do break up y’all still gon talk

Mfn still Texting me even though he got a girlfriend

Mfn by My-forever Nigga September 30, 2018

MFN method

My fucking nuts method

Most commonly used when tricking a friend about a form of Pokémon shiny hunting

“Hey have you tried the MFN method?”

MFN method by not a mumkay October 9, 2021

mfn princess 👸🏻 

Bestest best friend and totally effin sweet friendship wife with a huge effin heart!! Total package!! Fantabulous woman! Gorgeous inside and out!!

You’re my mfn princess 👸🏻!!! Ilysm!!!

mfn princess 👸🏻 by mfn king 🤴🏻 September 5, 2022

mf'n 

Def: Slang; mother fuckin

Background: Danish, what danes would label friends who covet thy neighbors mother, used boat salesmen

whoppity mf'n do

I gotta take a mf'n dump. BAD.

mf'n by Mateo Rosita Jones January 8, 2005

MFNC 

an acronym for "Motha Fuckin Nigga Chut", Chut meaning vagina in Punjabi; essentially meaning "Motha Fuckin Nigga Vagina"

1. You're such a MFNC, get off my grill.

MFNC by MZSwagger July 7, 2011