Related Clues:

• Library warning
• Whisperer's reproof
• Turn the sound down, the Pope is ringing America
• Sound of silence?
• Quiet!
• ''Zip it!''
• Librarian's reminder
• 'Don't let them hear us!'
• "Stop your yakking!"
• Volume control?
• 'Stop talking!'
• "Too noisy!"
• Audible silencer
• Peremptory signal
• Quiet "Quiet!"