A combination of dude and man. Most likely used to catch someone's attention. Also, mostly used by highly intoxicated college students attending MS State.
Drunk 1: "Hold up, dumayne... two things, Josh you my boy, and two, yeaaaaahhhhh"
Drunk 2: "Thanks dude, you're drunk."
Damn, My Coon Is All Distored. It's All Duwayne's Fault.
Damn, I Should Have Known Duwayne Was Like This.
Duwayne Killed My Coon, Now It Has To Buried.
Stop StopStop, DUWAYNEEEEEEEE