duh

Example:Gasp! That exam was obvious, a duh moment!

Definition:a sudden noisy breath or inhalation, often in surprise, dismay, or horror

Example:Pfft, why didn’t you think of that sooner? Duh!

Definition:an expression of contempt or disbelief, particularly when something is considered obviously wrong

Example:Uhh, why didn't you tell me we had a meeting? Duh!

Definition:an expression of uncertainty or lack of knowledge, sometimes followed by a duh to indicate realization