The most common and most likely answer to this crossword clue is the 9 letter word REFORMING
I've seen this crossword clue in The Daily Telegraph
R
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More clues leading to the result REFORMING
Buddy explains!
The straight part
We know that "Changing" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case changing = reforming.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 REFORMING mean?
REFORMING verb- To put into a new and improved form or condition; to restore to a former good state, or bring from bad to good; to change from worse to better
- To return to a good state; to amend or correct one's own character or habits
- To form again or in a new configuration.
- Reformation
- A catalytic process, whereby short-chain molecules are combined to make larger ones; used in the petrochemical industry.