The most common and most likely answer to this crossword clue is the 9 letter word EPARCHIES
I've seen this crossword clue in Financial Times
E
P
A
R
C
H
I
E
S
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The straight part
We know that "found in Greek diocese" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case found in greek diocese = eparchies.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 EPARCHIES mean?
EPARCHIES noun- One of the districts of the Roman Empire at the third echelon
- One of the administrative sub-provincial units of post-Ottoman independent Greece
- In pre-schism Christian Church, name for a province under the supervision of the metropolitan
- In Eastern Christendom, diocese of a bishop