A duni is someone stupid or something you would call someone who has done/said something stupid, and is used alot in the area of Cheltenham.
"Shutup duni you dont know what your on about"
A small creature chronically suffers from schizophrenia since birth. A duni is very small, so is therefore used to describe something abnormally tiny.
person 1 "omg what a tiny keyboard!"
person 2 "oh it's duni sized!"
A guy who thinks some people stink. I emphasize on “some”
Duny says “ b….k people stink”