The most common and most likely answer to this crossword clue is the 9 letter word EXCHEQUER
I've seen this crossword clue in The Times
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More clues leading to the result EXCHEQUER
- Accounting department an old inspector reported
- Old monitor's spoken of finance office
- Former scrutineer, reportedly in Treasury department.
- Treasury reported former auditor
- State funds partner no longer one with place on the board
- Treasury’s former auditor given audition
- Letter given to speaker’s investigator in government department
- Previously promise to pay right state coffers
- Rex is upset about money order in accounts department
- Former auditor, from what we hear, in the Treasury
Buddy explains!

The straight part
We know that "Accounting department" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case accounting department = exchequer.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 EXCHEQUER mean?
EXCHEQUER noun- A treasury.
- An available fund of money, especially one for a specific purpose.
- To proceed against (a person) in the Court of Exchequer.