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3.
Noun - The name given to a close friend (aka homie) that is comatose at a party. When your dunny drinks too many roofy Coolattas at a party and can no longer communicate, he becomes a dunster.
Did you see the way that that fat girl made that blacked-out dude lick her beef curtains. What a fucking dunster he is.
by Phuk Bucket June 05, 2006
 
1.
Derived from Britain. To be completely and utterly illogical in an argumentative setting.
Dunster: I am strong, and I drink Coke all day. Therefore, Coke makes you strong.

Bob: That makes no sense Dunster.
by GG-Rob February 04, 2010
 
2.
A Dunster is some one who is dense in the worst way. A term derived from duns cap, and shyster. A term created in Canada for describing complete idiots.
Examples

That dunster cant complete a sentence

Fucking dunster couldn’t tie his/her shoes without help
by lude savage June 28, 2009