A already smoked thrown away Cigarette, that is on the floor or in a public ashtray, that a bum or homeless person picks up, relights and smokes.
Homeless bum jay walking around the hood, found a half smoked Bum Butt on the floor, he picked it up, re lit it, and smoked it.
by Rik0290 January 28, 2009
It's a poor person (bum), that takes (scabs) the last bit off the cigarette (butt) with a tiny bit of tobacco left in it that people usually drop on the ground once they are done with it.
''Ah man, got to work for the rest of the week and i'm broke as hell, i might have to be a butt bum for the week''
by adam096 December 22, 2009