mbf 

"Must be following" on Tumblr; maybe even Twitter.

First 20 to reblog will be promoted. MBF (inserttumblrnamehere).

mbf by sophiechloe January 7, 2012

MBF 

Acronym for Metro Best Friend

Yvi: Who's that guy over there with the v-neck?
Christine: That's just my MBF, JP.

MBF by TheJBCrew April 28, 2011

MBF 

An acronym for "Milky Bum Factor"

Anal perspiration caused by hot and humid conditions. Leaves one's bum feeling moist an unclean. The higher the MBF factor, the worse the milky bum feeling is.

Seriously, it is so hot & humid outside i think the MBF is at 9.5 today.

MBF by awefsvc July 14, 2010

MBF 

The term used between close friendships. MBF stands for Mega Best Friend.

Dylan: Hey you're my MBF
Mariam: You're my MBF too!

MBF by mari__ December 26, 2013

MBF 

Missionary Butt Fuck

Sarah: Oh my G I hurt so bad.

Jessica: Why's that?

Sarah: Well I let Steve missionary butt fuck me (MBF) and now I am afraid I will have to steal some of my grandma's diapers so I don't shit my pants.

MBF by two lips May 18, 2010

MBF 

Abbreviation for "must be fried." Said when someone says something so ridiculous, they must have been fried.

you- OMG i wanna see that movie! i had a dream i saw it, but i never actually saw it... this is like SO much fun!!!!!!!
me- damn you MBF.

MBF by NPENN GETS FRIED March 8, 2011

MBF 

married black female, same thing as mwf except she's black

looking for mbf to hook-up with this weekend, it's always been a fantasy of mine.

MBF by Chanticlear January 14, 2008