The most common and most likely answer to this crossword clue is the 9 letter word CHAPLAINS
I've seen this crossword clue in Financial Times
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More clues leading to the result CHAPLAINS
Buddy explains!
The straight part
We know that "Clergy" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case clergy = chaplains.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 CHAPLAINS mean?
CHAPLAINS noun- A member of a religious body (often, but not always, of the clergy) officially assigned to give pastoral care at an institution, group, private chapel, etc.
- A person without religious affiliation who carries out similar duties in a secular context.