Related Clues:

• "Pipe down!"
• Stunned response
• Stillness
• Gag
• Teacher's command
• "Quiet!"
• Hush
• 'Quiet down!'
• 'Shut your mouth!'
• Command to Sweet Charlotte
• Golden thing
• "Silence"
• Be silent
• 'Don't say a word!'
• Keep concealed, with 'up'