The most common and most likely answer to this crossword clue is the 10 letter word EXTINGUISH
I've seen this crossword clue in The Times
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More clues leading to the result EXTINGUISH
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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 EXTINGUISH mean?
EXTINGUISH verb- To put out, as in fire; to end burning; to quench
- To destroy or abolish something
- To obscure or eclipse something
- To bring about the extinction of a conditioned reflex
- To hunt down (a species) to extinction
- To die out.