It's an onomatopeia for a drum technique normally accompanying the conclusion of a cheesy joke or a comedy pratfall (where someone is made to look like an idiot by their own devising - such as falling on a banana skin they earlier discarded). It consists of two fast rimshots and a splash cymbal - producing the sound "badum tish".
#1: What does bees do if they don't want to drive?
#2: Dunno
#1: Wait at the buzz stop! Haha!
#2: Badum tish!
The onomatopoeic expression of a drum roll used when a drum kit is not readily available, or the user isn't musically inclined. More often than not to indicate or emphasise a pun or joke.
"What path does a crazy person take through the forest?"
"I don't know Rosie, what path does a crazy person take through the forest?"
Someone who is addicted to obtaining money and building wealth. A money addict and fanatic. Breadheads often work more than one full-time job, and some even participate in illicit activities to "obtain the bread".