The most common and most likely answer to this crossword clue is the 9 letter word CLEANSING
I've seen this crossword clue in Independent
C
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Buddy explains!

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 CLEANSING mean?
CLEANSING verb- To free from dirt; to clean, to purify.
- To spiritually purify; to free from guilt or sin; to purge.
- The process of removing dirt, toxins etc.
- That cleanses.