The most common and most likely answer to this crossword clue is the 10 letter word CHASTISING
I've seen this crossword clue in The Times
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The straight part
We know that "Rebuking" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rebuking = chastising.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CHASTISING mean?
CHASTISING verb- To punish (someone), especially by corporal punishment.
- To castigate; to severely scold or censure (someone).
- To lightly criticize or correct (someone).