The most common and most likely answer to this crossword clue is the 8 letter word NATURISM
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result NATURISM
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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 NATURISM mean?
NATURISM noun- The belief in or practice of going nude in social settings, often in mixed-gender groups, specifically either in cultures where this is not the norm or for health reasons.
- The worship of the powers of nature.