A shirtless drunk wearing the Australian flag as a cape as a sign of patriotism. Female equivalent often wears the flag as a dress or bikini.

Commonly sighted at fireworks displays and brawls.
"What happened to your car?"
"Captain Australia jumped on the roof shouting "Aussie Aussie Aussie, Oi Oi Oi!"
by bluegirl January 31, 2008
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