The sound that emanates from a truck with air brakes at traffic lights just before they start rolling.
Man... I was at the light next to this BEAST of a semi... the light turned green and the BRAKE FART that rolled out from under there nearly blew me into the back seat of the car!!!!
by Bonemanrides October 11, 2016
When a man says he will "break your fart box" that means that he is planning on interduesing you to rough and painful anal sex. When a female says that, that means at some point she will force an object ( most of the time large) in to your anal cavity.
by Rocksaw_fartbox36 October 6, 2019