Ah duh is an expression used when something bad/annoying happens to yourself or a person near to you but it can be viewed in a funny light.

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.

Anatidaephobia is defined as a pervasive, irrational fear that one is being watched by a duck. The anatidaephobic individual fears that no matter where they are or what they are doing, a duck watches.

Anatidaephobia is derived from the Greek word "anatidae", meaning ducks, geese or swans and "phobos" meaning fear.

"Ah-Duh" is a combination of the "Ah-Hah" moment of realization and the "Duh!" moment of having realized something that should have already been obvious. Ah-Duh therefore captures the feeling one has when one excitedly realizes the obvious and/or believes they've had sudden insight but then realizes they have "re-realized" something they already knew to be the case.

THE BEST WORD EVER
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