A fork of Rural Dictionary
Young homeless people and panhandlers who congregate around Mill Avenue in downtown Tempe, Arizona. Though often used as a derogative term, it is also used by the street people to describe themselves. Probably coined as a variant of mallrat, with "mall" replaced by Mill Avenue.
Those panhandlers aren't ASU students, dude, they're Millrats.
To panhandle. A contraction of "spare change", used primarily Millrats.
That guy made $20 in a half-day of spainching.