Derived from "ah damn", ah duh was thought to be a more lighthearted expression.
Pronounced "ah duurh", usually used in a combination with a hand gesture of the palm facing up with fingers locked into a "semi-claw" position.
Person 2 *hand gesture* + "Ah duh"
Alternatively once the word is understood, the hand gesture may be used in a singular form.
It can be used it everyday conversation like you wouldn't belive
You can use it when you as another word for dumb, to just yell it in the halls, to make people laugh, just for the hell of it,to make fun of some,define a noun,it can honestly mean anything etc
The weather is a little on the ahduh side bro
Dude lets try and not be a ahduh today
My friends are a bunch of AHDUH