The most common and most likely answer to this crossword clue is the 9 letter word RELIGIOUS
I've seen this crossword clue in The Guardian
R
E
L
I
G
I
O
U
S
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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 RELIGIOUS mean?
RELIGIOUS noun- A member of a religious order, i.e. a monk or nun.
- Concerning religion.
- Committed to the practice or adherence of religion.
- Highly dedicated, as one would be to a religion.