Related Clues:

• ''Put a lid on it!''
• Shut up
• Librarian's admonition
• ''Quiet!''
• 'Be quiet!'
• 'Zip your lip!'
• When repeated, not to be repeated
• Recital rebuke
• Mum's the word
• Audience utterance
• "Pipe down!"
• Stunned response
• Stillness
• Teacher's command
• Cry hidden seven times elsewhere in this puzzle