The most common and most likely answer to this crossword clue is the 8 letter word PARGANAS
P
A
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G
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Buddy explains!
The straight part
We know that "parts of zillah" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case parts of zillah = parganas.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 PARGANAS mean?
PARGANAS noun- An administrative unit of India, consisting of a number of villages.