IPA: //ˌmɪsˈdiːd//
KK: /ˈmɪsˌdid/
An action that is wrong or illegal; a wrongdoing.
He was punished for his misdeed at school.
Misdeed → It is formed from "mis-" (meaning wrong or badly) and "deed" (from Old English "dǣd", meaning action or act). The word "misdeed" refers to an action that is wrong or bad.
Think of 'mis-' meaning wrong and 'deed' meaning action — a misdeed is simply a wrong action.