The most common and most likely answer to this crossword clue is the 10 letter word ATTENUATES
I've seen this crossword clue in Independent
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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 ATTENUATES mean?
ATTENUATES verb- To reduce in size, force, value, amount, or degree.
- To make thinner, as by physically reshaping, starving, or decaying.
- To become thin or fine; to grow less.
- To weaken.
- To rarefy.
- To reduce the virulence of a bacterium or virus.
- To reduce the amplitude of an electrical, radio, or optical signal.
- (of a beer) To become less dense as a result of the conversion of sugar to alcohol.