when you sit in your car and turn the heat all the way up and leave it there and just sit in your car with your homies and stay in there til you sweat. mostly performed in the winter
nigga its so fucking cold out lets fuckin' heat box nigga
by tieler davidson October 30, 2007
a small bathroom with no circulation like in a college dorm.
"Yo I'm about to take a dump in the heatbox ill be right back"
by heatbox101 September 01, 2009