The most common and most likely answer to this crossword clue is the 9 letter word ANNOUNCER
I've seen this crossword clue in Independent
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More clues leading to the result ANNOUNCER
- Newscaster: can one run broadcast?
- Female cat beginning to ruffle person behind mike
- Speaker on box perhaps runs after female cat
- Bringer of information one can run off
- One new, lightweight, er … bloke on TV?
- Newsreader can run one broadcast
- Can one run broadcast?
- Presenter can run one ragged
- In a river, heartless Nelson has what he needs to weigh anchor
- Radio station employee can run one off
Buddy explains!

The straight part
We know that ", woman has decapitated nightclub employee (9)" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case , woman has decapitated nightclub employee (9) = announcer.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 ANNOUNCER mean?
ANNOUNCER noun- One who makes announcements.