Acronym for 'Best Friend's Brother'. Just like in Victorious Justice's song "Best Friend's Brother" where she constantly says "My Best Friend's Brother is the one for me." and then says "BFB!! BFB!!"
"My Best Friend's brother is the one for me! YEAHYEAHYEAH! A Punk rock drummer and he's 6 foot 3! ... BFB! BFB! My best friend's brother, my best friend's brother!"-Victoria Justice
by DipnShablam November 29, 2011

by Straight outta da BRONX February 2, 2019

Jason: "Hey Sofia, Do you wanna be my BFB!"
Sofia: "Only if you get a word on Urban Dictionary"
Jason: "DEAL"
Sofia: "Only if you get a word on Urban Dictionary"
Jason: "DEAL"
by MyMonsterDK October 7, 2020

by nuttinglos May 21, 2018

Boobs From Behind. A fortunate combination of svelte torso and large endowment that allows the outside curves of a woman's breasts to be seen from a vantage point behind the woman.
BFB's are a very desirable trait.
BFB's are a very desirable trait.
"Bro, I can't wait for that chick in front of the line to pay and turn-around. Even her BFB's are awesome."
by jt_twit October 7, 2009

by BFB4lyfe December 29, 2010
