Duder is a word of many possibilites. It can be used as a replacement for dude. It can also be used to mean someone is more dude-like than someone else (as in dude, duder, dudest.) It has also been known to be used to describe objects for which the name has been temporarily forgotten, or otherwise unknown to the user of the word. Still yet another usage is a verb which means the act of being a dude or doing dudely things.
Hey duder, come over to my house.

Steve is duder than I am, but surely not the dudest guy in the room.

Beth need help to figure out how to opperate this new duder she got.

I think I'm going to go put on my sunglasses and duder around town.
by cool4dude May 1, 2005
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n. 30-something guy, young professional, wearing diagonally/vertically striped button-down (slightly wrinkled), looking to score beyond his station with aims at 20-something girls. Hair product content=high, intellectual capacity=low.
With hair that is perfectly styled but looks slightly mussed and jeans that appear old and rumpled, but are actually brand new and over-priced, the duder walked into the bar that he had read was uberhip hoping to score.
by librarywoman November 27, 2006
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usually used when describing a male, a new pronoun that can be a subject, direct object or indirect object - may also be used for females and pretty much anything as long as the meaning is described in context
Yo duder, what's up? I'm heading down to the board shop to get this little duder fixed. I smashed up the nose on a mean duder. Tranlation: Yo man, what's up? I'm heading down to the board shop to get my board fixed. I smashed up the nose on a big wave.
by Duncan Jones September 14, 2007
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When a girl is giving a guy head (or guy going down on a girl) and the guy guides the girl's head up and down his dick by sticking his pointer and middle fingers in her nose like a bowling ball. This is in reference to "the dude" from The Big Lebowski. Afterwords, the girl cooks the guy pancakes.
Sally was sucking dick at sucking dick so I took control and gave her a duder. Then that bitch made me some pancakes.
by Bobby Budnick July 26, 2011
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A male, a dude, particularly a dude whos name is unknown, according to Shawn.
Shawn: Look at that duder...he thinks he is cool in that ricer...
Ben: Yeah, ricers suck...look at that chick in the pick-em-up truck!
by knechel May 22, 2006
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