an adjective which can be placed in front of any word and used to describe anything at all. can be interpreted as a good description of something and interpreted postively or negatively.
Jane: Wow Pete, that shirt is sooo duppy!
Pete: Uh, does that mean you like it or...?
Jane: It can mean whatever you want it to mean!
Pete: So it's a cool shirt, then?
Jane: Well, to you its duppy, to me its duppy, and its all a different kind of duppy.
Pete: Uhh, ok then. Duppy!