This term is coined from the 1992 Film "The Fly" starring Jeff Goldblum.

Someone has Brundlebreath when their breath is fowl and smells like feces and chunks of rotten flesh. Typicallys the victim is somehow completely oblivious to the fecal stench that emanates from their mouth.
We were going to have lunch but the dude in the car had Brundlebreath so bad he fumed us out and we were all left feeling nauseous.
by Hunkasaurus Chunk May 5, 2009
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