The most common and most likely answer to this crossword clue is the 11 letter word OVERTURNING
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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 OVERTURNING mean?
OVERTURNING verb- To turn over, capsize or upset.
- To overthrow or destroy.
- To reverse (a decision); to overrule or rescind.
- To diminish the significance of a previous defeat by winning; to make a comeback from.
- The act by which something is overturned.