Originated from the term 'Plastered', but replaced with the Australian proprietary eponym for plasterboard, being Gyprock, an Australian plasterboard company.
Stevo got was absolutely Gyprocked last night, he was laying on the floor by 12.
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".