The most common and most likely answer to this crossword clue is the 8 letter word SILENCER
I've seen this crossword clue in The Daily Telegraph
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More clues leading to the result SILENCER
- One suppressing inconvenient report on firing?
- Means to suppress report
- Reclines, flopping in part of car
- Something traditionally golden, right, in part of firearm?
- License crazy Republican to manufacture device for a gun
- It’s nicer, mostly less windy – yet muffler’s required
- Sincere about limiting length of exhaust attachment
- A car spares outlet may have one over a barrel!
- One helps to hush up a report
- Muffler acquired by nieces playing around lake and river
Buddy explains!

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 SILENCER mean?
SILENCER noun- Something that silences.