Related Clues:

• "Knock it off!"
• Librarian's plea
• "Uncle!"
• 'Shut your mouth!'
• Library imperative
• "I give!"
• Command to Sweet Charlotte
• "When!"
• "Silence"
• Be silent
• 'Don't say a word!'
• ''Stifle!''
• ''Be still!''
• Keep concealed, with 'up'
• 'Put a sock in it!'