Castigate, admonish (6)
I believe the answer is:
rebuke
I believe this clue is a double definition.
'castigate' is the first definition.
(I know that castigate is a more specific form of rebuke)
'admonish' is the second definition.
(I've seen this in another clue)
(Other definitions for rebuke that I've seen before include "Sharply reprimand" , "Reprimand, admonish" , "Remonstration" , "Sharply criticize" , "Express sharp disapproval" .)