1 definition by Str8sk8r

Top Definition

The act of not fully wiping after dropping a duece and then commencing to fart in a persons general direction. sending tiny feces shrapnel everywhere.

Holy shit! He just left off a huge butt grenade.

look out, a butt grenade!

by Str8sk8r June 14, 2010

Buy a Butt grenade mug!