The most common and most likely answer to this crossword clue is the 7 letter word SILENCE
I've seen this crossword clue in The Times
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More clues leading to the result SILENCE
- Gag vacuously lame, considering skirting round it?
- Quiet, because sleep regularly has to be protected
- Gag first couple from Lebanon, smuggled in after
- Offend Anglicans, passing round half of lewd gag
- Hamlet’s rest? As interrupted by the French
- Peaceful situation for Hamlet’s rest?
- Peace in the time following admitting the French
- The French in immoral act with church saying nothing
- Quiet nieces dancing left inside
- Peace after getting round the French
Buddy explains!

The straight part
We know that "Gag" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case gag = silence.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 SILENCE mean?
SILENCE noun- The absence of any sound.
- The act of refraining from speaking.
- Form of meditative worship practiced by the Society of Friends (Quakers); meeting for worship.
- To make (someone or something) silent.
- To repress the expression of something.
- To suppress criticism, etc.
- To block gene expression.
- Murder
- Be silent.