A marvelously useful syllable that indicates that the statement immediately preceding is blatantly obvious, or that the preceding question has a blatantly obvious answer.
'Will Connecticut Republicans nominate for the Senate a former congressman with a reputation for bipartisanship, or a businesswoman whose claim to fame is building a professional wrestling empire? Duh."
An exclamation used to make any statement true.
The earth is flat, DUH!
Trying to explain a song to someone.
"You know, that song. The "DUH DUH DUH DUHHHH" one."
The pussy way of saying the phrase, "No shit."
Often used by twelve year olds around their parents due to the fact that they're not allowed to cuss.
Random 12 year old: Guess what! Spiderman shoots spider webs!
Other random 12 year old: No duh.
15 year old: Pussies.
A phrase used when something of great ecxellence is hapening. Usually followed by pointing one finger to the ground and rotating it.
Two guys walk into a bar. A hot chick goes up to one of the guys and asks if he wants head. He would look at his friend, say duh and spin his twirling towards the ground.