The most common and most likely answer to this crossword clue is the 9 letter word DEACONESS
I've seen this crossword clue in The Times
D
E
A
C
O
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S
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The straight part
We know that "Ecclesiastical female" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case ecclesiastical female = deaconess.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 DEACONESS mean?
DEACONESS noun- A female deacon.
- A female servant in the early Christian church.
- The nun in charge of the altar in a convent.
- One of an order of women in some Protestant churches who nurse the sick and tend the poor.