Related Clues:

• Sound from a silencer
• "No more talking!"
• ''Keep quiet!''
• Restraining order
• Impose quiet
• ''Stop talking!''
• 'Quiet, you!'
• Reaction to a big library volume?
• 'Not so loud!'
• 'Keep it down'
• "Keep it down!"
• Usher's admonition
• 'This is a library!'
• Library admonition
• Finger-on-lips sound