look up any word, like cunt:
 
3.
"Big Fat Nasty Boobies"
That girls shirt was way to tight for the size she was, instead she should have been wearing a rain coat to cover up those BFNB's.
by Ryan, Ross, Josh September 10, 2006
 
1.
Brake for nothing Bitch.

What I call people(mostly women)who are a
mile behind a car but are always touching
the brakes.
You F-ing BFNB. xxxxxxxxxx
by Jcat January 13, 2005
 
2.
Big Fat Nasty Bottom

A homosexual gentleman who prefers to receive phallus in the booty during the act of intercourse. Can be used in either a derogatory or jocular manner.
"The gentleman that I had the fortune to woo yesterday evening was a mighty BFNB."
"Indeed."
by Didactic Instructional December 29, 2013