Related Clues:

• Library sign
• Like some partners
• Toned down
• Hush
• Silenced
• 'Zip it!'
• Silenced the tube
• Closed up
• Unvoiced
• 'Put a sock in it!'
• Whispered
• Angry teacher's cry
• Stifled
• "Put a sock in it!"
• Peacefully silent