It is a swift comment simply informing you that you lack any knowledge you have about the situation.
Darnel: ere blud check ma new ting.
Adeolu: ere fam is that fresh.
Darnel: ya Dun No!
Adeolu: I Dun No?
Darnel: Dun No Dun No Dun No.
by Nathan Pacey September 20, 2008
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When a person can't get himself to talk about a certain ongoing subject (normally on chatrooms) and is put in a awkward situation, where some might expect a reaction from him and he goes,

"dun dun."

It comes from "so done with this". Usually related with Otaku culture for some reason.
Person 1: I just raped this bitch so fucking good, i swear i did.

Person 2: Hahaha so funny!

Person 3. o.o.. dun dun
by TheWanAndOnly December 19, 2013
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When you are in your room nuching your flanders and suddenly you realize that you forgot to shut your blinds and your neibor who is cutting the grass can see you and you're like...o man i'm dun
5 piece dun!! 10 piece dun!! o man I'm dun Want some dun? Yer dun!!
by Mark Nuch September 19, 2005
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the state a person is in after finding out or witnessing something that they probably wouldn't want to know or witness, or finding out or witnessing something extremely funny or startling
He was dun! when he found out she was an intersex.
by The Onlyone Xerox April 9, 2007
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1.) Windows dialer- Dial Up Networking

2.) What you should Git r!
I am currently connected to the internet through DUN

Hey, Larry.
by BObo D. HObo June 19, 2005
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a stupd person or group of stupid people
james: yo look at my new K Swiss
Zach: Nobody wears K Swiss you dun da dun!
by zzz zzz August 26, 2009
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Dun+Did
A phrase similar to the terms "fucked" and "screwed", which generally means your out of luck.
"awww shiiiiit, you DUN did it now!"
"haha, that foo got DUN did!"
by rihx December 4, 2003
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