grundle duster Share definition Flag a strip of hair on the chin usually worn by men who are gay or a few appletinis away from sucking a dick I think that guy is gay, he's drinking an appletini and has a grundle duster. grundle duster by King of the Diner Whores August 23, 2007 0 0 Get merch Get the grundle duster mug. Buy Now — $32.95 See more merch