Being tired out. Having low energy. In reference to the 2016 presidential Republican candidate Jeb Bush who through his campaign displayed very low levels of energy.
I don't think I'll be able to finish this assignment on time. I'm so jebbed out, I just want to sleep all day.
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".