ㅂㄷㅂㄷ /bu-deul-bu-deul/
Trembling / Shaking with anticipation
Represents trembling or shaking — short for 부들부들 (quivering). Used to express excitement, nervousness, or barely-contained anger.
Examples
결과 기다리면서 ㅂㄷㅂㄷ
Shaking while waiting for the results ㅂㄷㅂㄷ
화나서 ㅂㄷㅂㄷ함
So angry I'm literally trembling