This is the 10072nd most frequent Spanish word.
castigado
Punished.
Here, 'castigado' is used as the past participle of 'castigar' to denote an action undergone by the subject.
El niño fue castigado por romper la ventana.
The child was punished for breaking the window.
In this case, 'castigado' conveys a warning of a potential consequence, referring to a state resulting from a hypothetical punishment.
Si sigues actuando de esa manera, terminarás castigado.
If you keep acting that way, you'll end up punished.
Here, 'castigado' describes the student's status as a result of disciplinary action.