The most common and most likely answer to this crossword clue is the 9 letter word DEAFENING
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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 DEAFENING mean?
DEAFENING verb- To make deaf, either temporarily or permanently.
- To make soundproof.
- (sometimes figurative) To stun, as with noise.
- Pugging
- The process by which something is deafened.
- Loud enough to cause temporary or permanent hearing loss.
- Very loud.