The most common and most likely answer to this crossword clue is the 9 letter word OBSESSION
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More clues leading to the result OBSESSION
- Meeting of alumni? There’s a thing
- Crime occurring without judge hearing a thing
- Bishop joining meeting fronted by old bag?
- Complex old boy overlooking meeting
- One working under dodgy bosses reveals hang-up
- Period of working on hobby regularly a compulsion
- Regularly lobby meeting with passion
- Thing is, sweetheart, boss is busy working
- Bug old boy before meeting
- Thing old bishop put down before sitting
Buddy explains!

The straight part
We know that "hang-up" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case hang-up = obsession.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 OBSESSION mean?
OBSESSION noun- A compulsive or irrational preoccupation.
- An unhealthy fixation.
- Influence or control by evil spirits without possession.