The most common and most likely answer to this crossword clue is the 7 letter word SOFTENS
I've seen this crossword clue in The Daily Telegraph
S
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F
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More clues leading to the result SOFTENS
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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 SOFTENS mean?
SOFTENS verb- To make something soft or softer.
- To undermine the morale of someone (often soften up).
- To make less harsh
- To become soft or softer